EXAS EXACT Sciences Corporation

DESCRIPTION OF THE NOTES

              In January 2018, we issued $690 million aggregate principal amount of our 1.0% Convertible Senior Notes due 2025 (the "initial notes") under a base indenture dated as of January 17, 2018 (the "base indenture") between us and U.S. Bank National Association, as trustee (the "trustee"), as supplemented by a supplemental indenture dated as of January 17, 2018 between us and the trustee (the "supplemental indenture" and, together with the base indenture, the "indenture"). The terms of the notes include those expressly set forth in the indenture and those made part of the indenture by reference to the Trust Indenture Act of 1939, as amended, which we refer to as the Trust Indenture Act.

              We will issue the 1.0% Convertible Senior Notes due 2025 offered hereby pursuant to the indenture (the notes offered hereby, together with the initial notes, the "notes"). The notes offered hereby will have identical terms, and will have the same CUSIP number, as the initial notes. The initial notes and the notes offered hereby will be treated as a single series of securities for all purposes under the indenture, including, without limitation, waivers, amendments and offers to purchase. Holders of the initial notes, the notes offered hereby and any additional notes of the same series that we issue in the future pursuant to the indenture will vote as one class under the indenture.

              The following description is only a summary of the material provisions of the notes and the indenture and does not purport to be complete. This summary is subject to, and is qualified by reference to, all the provisions of the notes and the indenture, including the definitions of certain terms used in the indenture. We urge you to read the indenture in its entirety because it, and not this description, defines your rights as a holder of the notes. You may request a copy of the indenture as set forth under the caption "Where You Can Find More Information."

              For purposes of this description, references to:

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"the Company," "we," "our" and "us" refer only to Exact Sciences Corporation and not its subsidiaries;



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"business day" refers to any day other than a Saturday, a Sunday or a day on which the Federal Reserve Bank of New York is authorized or required by law or executive order to close or be closed;



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"close of business" refer to 5:00 p.m., New York City time, and "open of business" refer to 9:00 a.m., New York City time;



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"common stock" refer to our common stock, par value $0.01 per share; and



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"notes" refer to each $1,000 principal amount of 1.0% Convertible Senior Notes due January 15, 2025 issued on January 17, 2018 and offered hereby.

              Unless the context otherwise requires, all references to interest in this prospectus supplement include additional interest, if any, payable at our election as the sole remedy relating to the failure to comply with our reporting obligations pursuant to the provisions set forth below under the heading "—Events of Default; Notice and Waiver."

              References in this prospectus supplement to a "holder" or "holders" of notes that are held through DTC are references to owners of beneficial interests in such notes, unless the context otherwise requires. However, we and the trustee will treat the person in whose name the notes are registered (Cede & Co., in the case of notes held through DTC) as the owner of such notes for all purposes.

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Brief Description of the Notes

              The notes will:

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be our general, unsecured obligations;



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bear cash interest at a rate of 1.0% per year, payable semi-annually in arrears, on January 15 and July 15 of each year, commencing on July 15, 2018;



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subject to satisfaction of certain conditions and during the periods described below, be convertible by you at any time prior to the close of business on the second scheduled trading day (as defined below) immediately preceding the maturity date, as described under "—Conversion Rights," into cash, shares of our common stock or a combination of cash and shares of our common stock, at our election, based on an initial conversion rate of 13.2569 shares of our common stock per $1,000 principal amount of notes (subject to adjustment as set forth in "—Conversion Rights—Conversion Rate Adjustments" below), which represents an initial conversion price of approximately $75.43 per share. In the event of a make-whole fundamental change (as defined below), we will, under certain circumstances, increase the conversion rate as described herein;



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not be subject to redemption at our option prior to maturity;



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be subject to repurchase by us at your option if a fundamental change (as defined below) occurs, at a cash repurchase price equal to 100% of the principal amount of the notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date, as set forth under "—Fundamental Change Put" and



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mature on January 15, 2025 unless earlier converted or repurchased by us at your option.

              The indenture does not limit the amount of debt that may be issued by us or our subsidiaries under the indenture or otherwise. Neither we nor any of our subsidiaries will be subject to any financial covenants under the indenture. In addition, neither we nor any of our subsidiaries will be restricted under the indenture from paying dividends, incurring debt or issuing or repurchasing our securities. You are not afforded protection under the indenture in the event of a highly leveraged transaction or a change in control of us, except to the extent described below under "—Conversion Rights—Adjustment to Conversion Rate Upon a Make-Whole Fundamental Change," "—Fundamental Change Put" and "—Consolidation, Merger and Sale of Assets."

              The initial notes are not listed or quoted, and we do not intend to apply to have the notes listed or quoted, on any securities exchange or any automated quotation system.

              The notes initially will be issued in book-entry form only in minimum denominations of $1,000 principal amount and whole multiples of $1,000 in excess thereof. Beneficial interests in the notes will be shown on, and transfers of beneficial interests in the notes will be effected only through, records maintained by The Depository Trust Company, or DTC, or its nominee, and any such interests may not be exchanged for certificated notes except in limited circumstances. For information regarding conversion, registration of transfer and exchange of global notes held in DTC, see "—Form, Denomination and Registration—Global Notes, Book-Entry Form."

              If certificated notes are issued, you may present them for conversion, registration of transfer and exchange, without service charge, at our office or agency, which will initially be the office or agency of the trustee.

              If any interest payment date, the maturity date, any earlier required repurchase date upon a fundamental change or any other due date for a payment on a note falls on a day that is not a business day, the required payment will be made on the next succeeding business day and no interest on such payment will accrue in respect of the delay.

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Additional Notes

              We may, without the consent of, or notice to, the holders of the notes or the initial notes, issue additional notes under the indenture in the future on the same terms and conditions as the notes offered hereby (other than differences in the issue price and interest accrued prior to the issue date of such additional notes) in an unlimited aggregate principal amount; provided that if any such additional notes are not fungible with the notes initially offered hereby for U.S. federal income tax purposes, such additional notes will have one or more separate CUSIP numbers. The notes offered by this prospectus supplement, the initial notes and any additional notes would rank equally and ratably and would be treated as a single series for all purposes under the indenture. No additional notes may be issued if any event of default has occurred with respect to the notes.

Payment at Maturity

              On the maturity date, each holder will be entitled to receive on such date $1,000 in cash for each $1,000 in principal amount of notes, together with any accrued and unpaid interest to, but excluding, the maturity date, unless earlier converted or repurchased by us at the holder's option. With respect to global notes, we will pay or cause the paying agent to pay principal and any interest to DTC in immediately available funds. With respect to any certificated notes, principal and any interest will be payable at our office or agency, which initially will be the office or agency of the trustee.

Interest

              The notes will bear cash interest at a rate of 1.0% per year until maturity. Interest on the notes will accrue from January 17, 2018 or from the most recent date on which interest has been paid or duly provided for. We will pay interest semi-annually, in arrears on January 15 and July 15 of each year, commencing on July 15, 2018, to holders of record at the close of business on the preceding January 1 and July 1, respectively.

              We will pay or cause the paying agent to pay interest on:

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global notes to DTC in immediately available funds;



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any certificated notes having a principal amount of less than $2,000,000, by check mailed to the holders of those notes; and



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any certificated notes having a principal amount of $2,000,000 or more, either by check mailed to each holder or, upon application by such holder to the registrar not later than the relevant record date, by wire transfer in immediately available funds to that holder's account within the United States, which application shall remain in effect until the holder notifies, in writing, the registrar to the contrary.

              Interest will be calculated on the basis of a 360-day year consisting of twelve 30-day months and, for partial months, on the number of days actually elapsed in a 30-day month.

              If any interest payment date, the maturity date or any earlier required fundamental change repurchase date of a note falls on a day that is not a business day (which for these purposes, "business day" shall not include days in which the office where the place of payment is authorized or required by law to be closed), the required payment will be made on the next succeeding business day and no interest on such payment will accrue in respect of the delay.

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Ranking

              The notes will be our senior unsecured obligations that will:

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rank senior in right of payment to all of our future indebtedness that is expressly subordinated in right of payment to the notes;



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rank equally in right of payment to all of our future liabilities that are not so subordinated;



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be effectively junior to all of our existing and future secured indebtedness and other secured obligations, to the extent of the value of the assets securing that indebtedness and other secured obligations; and



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be structurally subordinated to all indebtedness and other liabilities (including trade payables) of our subsidiaries.

              The indenture will not limit our ability to incur additional indebtedness in the future, including senior secured indebtedness, and such indebtedness may be substantial. In the event of our bankruptcy, liquidation, reorganization or other winding up, our assets that secure secured indebtedness will be available to pay obligations on the notes only after all such secured indebtedness has been repaid in full from such assets. We advise you that there may not be sufficient assets remaining to pay amounts due on any or all the notes then outstanding.

              As of March 31, 2018, our total consolidated indebtedness (including the outstanding principal amount of the initial notes) was approximately $694.4 million, $4.4 million of which was secured. As of March 31, 2018, our subsidiaries had $8.3 million of indebtedness and other liabilities (including trade payables). After giving effect to the issuance of the notes offered hereby (assuming no exercise of the underwriters' option to purchase additional notes), our total consolidated indebtedness would have been approximately $884.4 million as of March 31, 2018.

              The ability of our subsidiaries to pay dividends and make other payments to us is restricted by, among other things, applicable corporate and other laws and regulations as well as agreements to which our subsidiaries are currently or may in the future become a party. We may not be able to pay accrued interest, the cash portions of any settlement amount upon conversion of the notes, the fundamental change repurchase price upon a fundamental change if a holder requires us to repurchase notes as described below or principal due on the maturity date. See "Risk Factors—Risks Relating to Our Indebtedness and the Notes—We may not have the ability to raise the funds necessary to settle conversions of the notes or to repurchase the notes for cash when required by the holders upon a fundamental change."

No Redemption

              We may not redeem the notes prior to the maturity date, and no sinking fund is provided for the notes, which means that we are not required to redeem or retire the notes periodically.

Conversion Rights

              Prior to the close of business on the business day immediately preceding July 15, 2024, you may convert all or a portion of your notes only upon the satisfaction of one or more conditions described below under "—Conversion Upon Satisfaction of Sale Price Condition," "—Conversion Upon Specified Corporate Transactions," "—Conversion Upon a Fundamental Change" and "—Conversion Upon Satisfaction of Trading Price Condition." You may convert fewer than all of your notes so long as the notes converted are an integral multiple of $1,000 principal amount.

              Holders may convert, at their option, their notes based on an initial conversion rate of 13.2569 shares of common stock per $1,000 principal amount of notes (equivalent to an initial

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conversion price of approximately $75.43 per share of our common stock). The conversion rate will be subject to adjustment as described below. As described under "—Settlement Upon Conversion," upon conversion, we will satisfy our conversion obligation with respect to the notes to be converted into cash, shares of our common stock or a combination of cash and shares of our common stock, at our election.

              The conversion rate and the equivalent conversion price in effect at any given time are referred to as the "applicable conversion rate" and the "applicable conversion price," respectively, and will be subject to adjustment as described below. The "applicable conversion price" at any given time will equal $1,000 divided by the applicable conversion rate at such time.

              Except as provided in the next paragraph, upon conversion, you will not receive any separate cash payment of accrued and unpaid interest on the notes. Accrued and unpaid interest to the conversion date is deemed to be paid in full with the cash paid and shares of our common stock issued, if any, upon conversion rather than cancelled, extinguished or forfeited. With respect to any conversion of the notes into a combination of cash and shares of our common stock, accrued and unpaid interest will be deemed to be paid first out of any cash paid upon such conversion. For a discussion of the tax treatment to you of converting your notes, see "Material U.S. Federal Income Tax Considerations."

              If you convert any notes after the close of business on the record date for an interest payment but prior to the corresponding interest payment date, you will receive on the earlier of the corresponding interest payment date and the date we deliver the consideration due in respect of such conversion, the interest accrued and unpaid on your notes, notwithstanding your conversion of those notes prior to the interest payment date, in the event you were the holder of record on the corresponding record date. However, except as provided in the next sentence, at the time you surrender your notes for conversion (whether or not you were holder of record), you must pay us an amount equal to the interest that has accrued and will be paid on the notes being converted on the corresponding interest payment date. You are not required to make such payment:

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if you convert your notes after the close of business on January 1, 2025 which is the regular record date immediately preceding the maturity date;



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if you convert your notes in connection with a fundamental change and we have specified a fundamental change repurchase date that is after a record date and on or prior to the business day immediately following the corresponding interest payment date; or



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to the extent of any overdue interest, if overdue interest exists at the time of conversion with respect to your notes.

              Therefore, for the avoidance of doubt, all holders on the regular record date immediately preceding the maturity date and any fundamental change repurchase date will receive and retain the full interest payment due on the maturity date or other applicable interest payment date regardless of whether their notes have been converted following such record date.

              Except as described under "—Conversion Rate Adjustments," we will not make any payment or other adjustment for dividends on any common stock issued upon conversion of the notes.

              The trustee shall have no duty to monitor or notify the holders as to whether any of the conditions to conversion have occurred.

Conversion Upon Satisfaction of Sale Price Condition

              Prior to the close of business on the business day immediately preceding July 15, 2024, you will have the right to convert all or a portion of your notes at any time during any calendar quarter (and only during such calendar quarter) if the closing sale price of our common stock was more than 130% of the applicable conversion price on each applicable trading day for at least 20 trading days (whether

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or not consecutive) in the period of the 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter.

              The "closing sale price" of any share of our common stock on any trading day means:

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the closing sale price per share of our securities (or if no closing sale price is reported, the average of the closing bid and closing ask prices or, if more than one in either case, the average of the average closing bid and the average closing ask prices) on such trading day as reported in composite transactions for the relevant stock exchange (as defined below);



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if our common stock is not listed on a relevant stock exchange on such date, the last quoted bid price per share for our common stock in the over-the-counter market on such trading day as reported by OTC Markets Group Inc. or a similar organization; or



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if our common stock is not so quoted, the average of the mid-point of the closing bid and closing ask price per share of our common stock on such trading day as determined by a nationally recognized securities dealer retained by us for that purpose, which may include one of the underwriters.

              The closing sale price will be determined without reference to early hours, after hours or extended market trading.

              "Relevant stock exchange" means the NASDAQ Capital Market or, if our common stock is not then listed on the NASDAQ Capital Market, the principal other U.S. national or regional securities exchange on which our common stock is then listed.

              The term "trading day" means a day on which:

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trading in our common stock generally occurs on the relevant stock exchange or, if our common stock is not then listed on a relevant stock exchange, on the principal other market on which our common stock is then traded; and



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a closing sale price for our common stock is available on such securities exchange or market.

              If our common stock is not so listed or traded, "trading day" means a business day.

Conversion Upon Specified Corporate Transactions

              Prior to the close of business on the business day immediately preceding July 15, 2024, you will have the right to convert all or a portion of your notes if we:

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distribute to all or substantially all holders of our common stock any rights, options or warrants (other than pursuant to a stockholders rights plan) entitling them to purchase, for a period of 45 calendar days or less from the announcement date for such distribution, shares of our common stock at a price per share less than the average of the closing sale prices of our common stock for the ten consecutive trading day period ending on, and including, the trading day immediately preceding the announcement date for such distribution; or



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distribute to all or substantially all holders of our common stock cash or other assets, debt securities or rights to purchase our securities (other than pursuant to a stockholders rights plan), which distribution has a per share value, as reasonably determined by our board of directors or a committee thereof, exceeding 10% of the closing sale price of our common stock on the trading day immediately preceding the announcement date for such distribution.

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              In either case, we will notify you, the trustee and the conversion agent (if other than the trustee) at least 45 scheduled trading days (as defined below) prior to the ex-dividend date (as defined below) for such distribution. Once we have given such notice, a holder may convert all or a portion of its notes at any time until the earlier of the close of business on the business day immediately preceding the ex-dividend date and any announcement by us that such distribution will not take place. You may not convert any of your notes based on this conversion contingency if as a result of holding the notes you will otherwise participate in the distribution, without conversion as a result of holding the notes, at the same time and on the same terms as holders of our common stock as if you held a number of shares of our common stock equal to the applicable conversion rate on the record date of such distribution for each $1,000 principal amount of notes held by you (calculated on an aggregate basis per holder).

              "Scheduled trading day" means a day that is scheduled to be a trading day on the relevant stock exchange. If our common stock is not so listed or admitted for trading, "scheduled trading day" means a business day.

              "Ex-dividend date" means the first date on which the shares of our common stock trade on the applicable exchange or in the applicable market, regular way, without the right to receive the issuance, dividend or distribution in question from us or, if applicable, from the seller of our common stock on such exchange or market (in the form of due bills or otherwise) as determined by such exchange or market. For the avoidance of doubt, any alternative trading convention on the applicable exchange or market in respect of our common stock under a separate ticker symbol or CUSIP number will not be considered "regular way" for this purpose.

Conversion Upon a Fundamental Change

              Prior to the close of business on the business day immediately preceding July 15, 2024, if a fundamental change (as defined under "—Fundamental Change Put") occurs, or if we are a party to a consolidation, merger, binding share exchange, or sale, conveyance, transfer, lease or other disposition of all or substantially all of our and our subsidiaries' assets, taken as a whole, in each case, pursuant to which our common stock would be converted into reference property (as defined below) in a transaction described in "—Change in the Conversion Rights Upon Certain Reclassifications, Business Combinations, Asset Sales and Corporate Events," you will have the right to convert all or a portion of your notes at any time beginning on the effective date of such transaction or event until the earlier of (x) 35 trading days after the actual effective date of such transaction or event, or if such transaction or event also constitutes a fundamental change, until the related fundamental change repurchase date and (y) the second scheduled trading day immediately preceding the maturity date. We will notify you, the trustee and the conversion agent (if other than the trustee) of the effective date of any fundamental change no later than one business day after such effective date. If you convert your notes in connection with a fundamental change that is a make-whole fundamental change, we will, under certain circumstances, increase the applicable conversion rate by a number of additional shares, as described under "—Adjustment to Conversion Rate Upon a Make-Whole Fundamental Change."

              If you have submitted all or a portion of your notes for repurchase, unless you have validly withdrawn such notes in a timely fashion, your conversion rights with respect to the notes so subject to repurchase will expire at the close of business on the business day immediately preceding the fundamental change repurchase date, unless we default in the payment of the fundamental change repurchase price. If you have submitted any notes for repurchase, such notes may be converted only if you submit a valid withdrawal notice, and, if the notes submitted are evidenced by a global note, you comply with appropriate DTC procedures.

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Conversion Upon Satisfaction of Trading Price Condition

              Prior to the close of business on the business day immediately preceding July 15, 2024, you may convert all or a portion of your notes during the five business day period following any five consecutive trading day period (the "measurement period") in which the "trading price" per $1,000 principal amount of notes, as determined following a request by a holder of notes in accordance with the procedures described below, for each trading day of the measurement period was less than 98% of the product of the closing sale price of our common stock and the applicable conversion rate on such trading day.

              The "trading price" of the notes on any date of determination means the average of the secondary market bid quotations per $1,000 principal amount of notes obtained by the bid solicitation agent for $5,000,000 principal amount of the notes at approximately 3:30 p.m., New York City time, on such determination date from three independent nationally recognized securities dealers we select for this purpose, which may include one of the underwriters, provided that if three such bids cannot reasonably be obtained by the bid solicitation agent but two such bids are obtained, then the average of the two bids shall be used, and if only one such bid can reasonably be obtained by the bid solicitation agent, then that one bid shall be used. If the bid solicitation agent cannot reasonably obtain at least one bid for $5,000,000 principal amount of the notes from a nationally recognized securities dealer, or, in its reasonable judgment, the bid quotations are not indicative of the secondary market value of the notes, then, for purposes of the trading price condition only, the trading price of the notes will be deemed to be less than 98% of the product of the closing sale price of our common stock and the applicable conversion rate on such trading day. If (x) we are not acting as bid solicitation agent, and we do not instruct the bid solicitation agent to obtain bids when required (as described below), or if we so instruct the bid solicitation agent but the bid solicitation agent fails to carry out such instruction, or (y) we are acting as bid solicitation agent and we fail to make such determination, then, in either case, the trading price per $1,000 principal amount of the notes will be deemed to be less than 98% of the product of the closing sale price of our common stock and the applicable conversion rate on each day the bid solicitation agent or we, as applicable, fail to do so.

              The bid solicitation agent (if other than us) shall have no obligation to determine the trading price per $1,000 principal amount of notes unless we have requested such determination; and we shall have no obligation to make such request (or, if we are acting as bid solicitation agent, we shall have no obligation to determine the trading price) unless and until a holder of a note provides us with reasonable evidence that the trading price per $1,000 principal amount of notes would be less than 98% of the product of the closing sale price of our common stock and the conversion rate and such holder requests that we request that the bid solicitation agent determine or, if we are acting as bid solicitation agent, requests that we determine, the trading price of the notes. At such time, we shall instruct the bid solicitation agent (if other than us) to determine or, if we are acting as bid solicitation agent, we shall determine, the trading price of the notes for each trading day beginning on the next trading day and on each successive trading day until a trading day occurs on which the trading price per $1,000 principal amount of notes is greater than or equal to 98% of the product of the closing sale price of our common stock and the applicable conversion rate on such trading day. At such time as we direct the bid solicitation agent in writing to solicit bid quotations, we will provide the bid solicitation agent with the names and contact details of the three independent nationally recognized securities dealers we select, and we will direct those securities dealers to provide bids to the bid solicitation agent. If the trading price condition has been met, we will so notify the holders, the trustee and the conversion agent (if other than the trustee). If, at any time after the trading price condition has been met, the trading price per $1,000 principal amount of notes is greater than or equal to 98% of the product of the closing sale price of our common stock and the conversion rate for such date, we will so promptly notify the holders, the trustee and the conversion agent (if other than the trustee).

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              We will initially act as the bid solicitation agent. We may, however, appoint another person as the bid solicitation agent (including any of our affiliates) without prior notice to the holders of the notes.

Conversions on or after July 15, 2024

              On or after July 15, 2024 until the close of business on the second scheduled trading day immediately preceding the maturity date, you may, at your option, convert all or any portion of your notes, in multiples of $1,000 principal amount, at any time, regardless of the foregoing circumstances.

Conversion Procedures

Procedures to be Followed by a Holder

              If you hold a beneficial interest in a global note, to convert you must deliver to DTC the appropriate instruction form for conversion pursuant to DTC's conversion program and, if required, pay funds equal to interest payable on the next interest payment date to which you are not entitled and, if required, pay all taxes or duties, if any. As such, if you are a beneficial owner of the notes, you must allow for sufficient time to comply with DTC's procedures if you wish to exercise your conversion rights.

              If you hold a certificated note, to convert you must:

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complete and manually sign the conversion notice on the back of the notes or a facsimile of the conversion notice;



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deliver the completed conversion notice, which is irrevocable, and the notes to be converted to the conversion agent;



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if required, furnish appropriate endorsements and transfer documents;



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if required, pay funds equal to interest payable on the next interest payment date to which you are not entitled; and



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if required, pay all transfer or similar taxes, if any.

              The conversion date will be the date on which you have satisfied all of the foregoing requirements. The notes will be deemed to have been converted immediately prior to the close of business on the conversion date.

              We will pay any taxes or duties relating to the issuance or delivery of our common stock if you exercise your conversion rights, except that you will be required to pay any tax or duty that may be payable relating to any transfer involved in the issuance or delivery of the common stock in a name other than your own. Certificates representing common stock will be issued and delivered only after all applicable taxes and duties, if any, payable by you have been paid in full.

              If you have already delivered a repurchase notice as described under "—Fundamental Change Put" with respect to a note, you may not surrender that note for conversion until you have validly withdrawn the repurchase notice in accordance with the indenture, except as to a portion of your note that is not subject to such repurchase notice.

Settlement Upon Conversion

              Upon conversion, we may choose to pay or deliver, as the case may be:

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cash ("cash settlement");



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shares of our common stock ("physical settlement"); or

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•

a combination of cash and shares of our common stock ("combination settlement"), as described below.

              We refer to each of these settlement methods as a "settlement method."

              All conversions occurring on or after July 15, 2024 will be settled using the same settlement method and the same relative proportion of cash and/or shares of our common stock as all other conversions occurring on or after July 15, 2024. If we elect a settlement method for conversions occurring on or after July 15, 2024, we will inform holders and the trustee and the conversion agent (if other than the trustee) of the settlement method we have selected no later than July 15, 2024.

              With respect to conversions occurring prior to July 15, 2024, we will use the same settlement method (including the same relative proportion of cash and/or shares of our common stock) for all conversions occurring on the same conversion date, but we will not have any obligation to use the same settlement method with respect to conversions that occur on different conversion dates. That is, we may choose for notes converted on one conversion date to settle conversions in physical settlement, and choose for notes converted on another conversion date cash settlement or combination settlement. If we elect a settlement method, we will inform holders so converting and the trustee and the conversion agent (if other than the trustee) of the settlement method we have selected no later than the close of business on the second trading day immediately following the related conversion date.

              If we do not timely elect a settlement method, we will no longer have the right to elect cash settlement or physical settlement with respect to that conversion date, and we will be deemed to have elected combination settlement in respect of our conversion obligation, as described below, and the specified dollar amount (as defined below) per $1,000 principal amount of notes will be equal to $1,000. If we elect combination settlement, but we do not timely notify the conversion agent of the specified dollar amount per $1,000 principal amount of notes, such specified dollar amount with respect to that conversion date will be deemed to be $1,000.

              It is our current intent and policy to settle all conversions through combination settlement with a specified dollar amount of $1,000.

              The settlement amount will be computed as follows:

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if we elect physical settlement, we will deliver to the converting holder in respect of each $1,000 principal amount of notes being converted a number of shares of our common stock equal to the conversion rate (plus cash in lieu of any fractional share of our common stock issuable upon conversion);



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if we elect cash settlement, we will pay to the converting holder in respect of each $1,000 principal amount of notes being converted cash in an amount equal to the sum of the daily conversion values (as defined below) for each of the 30 consecutive VWAP trading days (as defined below) during the relevant observation period (as defined below); and



•

if we elect (or are deemed to have elected) combination settlement, we will pay or deliver, as the case may be, to the converting holder in respect of each $1,000 principal amount of notes being converted a "settlement amount" equal to the sum of the daily settlement amounts (as defined below) for each of the 30 consecutive VWAP trading days during the relevant observation period (plus cash in lieu of any fractional share of our common stock issuable upon conversion).

              If more than one note is surrendered for conversion at any one time by the same holder, the conversion obligation with respect to such notes shall be computed on the basis of the aggregate principal amount of the notes (or specified portions thereof to the extent permitted by the indenture) surrendered.

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              The "daily settlement amount," for each of the 30 consecutive VWAP trading days during the relevant observation period, shall consist of:

•

cash equal to the lesser of (1) the maximum cash amount per $1,000 principal amount of notes to be received upon conversion as specified (or deemed specified) by us in the notice specifying our chosen settlement method (the "specified dollar amount"), divided by 30 (such quotient, the "daily measurement value") and (2) the daily conversion value on such VWAP trading day; and



•

if the daily conversion value exceeds the daily measurement value, a number of shares of our common stock equal to (1) the difference between the daily conversion value and the daily measurement value, divided by (2) the daily VWAP for such VWAP trading day.

              The "daily conversion value" means, for each of the 30 consecutive VWAP trading days during the applicable observation period, 1/30th of the product of:

•

the conversion rate in effect on that VWAP trading day; and



•

the daily VWAP of our common stock on that VWAP trading day.

              The "daily VWAP" means, for each of the 30 consecutive VWAP trading days during the applicable observation period, the per share volume-weighted average price as displayed under the heading "Bloomberg VWAP" on Bloomberg page "EXAS <equity> AQR" (or its equivalent successor if such page is not available) in respect of the period from the scheduled open of trading until the scheduled close of trading of the primary trading session on such VWAP trading day (or if such volume-weighted average price is unavailable, the market value of one share of our common stock on such VWAP trading day reasonably determined, using a volume weighted average method, by a nationally recognized independent investment banking firm retained for this purpose by us). The "daily VWAP" will be determined without regard to after-hours trading or any other trading outside of the regular trading session trading hours.

              The "observation period" with respect to any note surrendered for conversion means:

•

if the relevant conversion date occurs prior to July 15, 2024, the 30 consecutive VWAP trading day period beginning on, and including, the second VWAP trading day immediately succeeding such conversion date; and



•

if the relevant conversion date occurs on or after July 15, 2024, the 30 consecutive VWAP trading day period beginning on, and including, the 32nd scheduled trading day immediately preceding the maturity date.

              "VWAP trading day" means a day on which:

•

there is no market disruption event; and



•

trading in our common stock generally occurs on the relevant stock exchange.

              If our common stock is not so listed or admitted for trading on any relevant stock exchange, "VWAP trading day" means a "business day."

              "Market disruption event" means:

•

a failure by the relevant stock exchange to open for trading during its regular trading session; or



•

the occurrence or existence prior to 1:00 p.m., New York City time, on any scheduled trading day for our common stock for more than one half-hour period in the aggregate during regular trading hours of any suspension or limitation imposed on trading (by reason of movements in price exceeding limits permitted by the relevant stock exchange or otherwise)

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in our common stock or in any options contracts or futures contracts relating to our common stock.

              Except as described under "—Adjustment to Conversion Rate Upon a Make-Whole Fundamental Change" and "—Change in the Conversion Rights Upon Certain Reclassifications, Business Combinations, Asset Sales and Corporate Events," we will deliver the consideration due in respect of conversion as follows:

•

if we elect physical settlement, (x) with respect to conversions occurring prior to the final regular record date preceding the maturity date, the third business day immediately following the relevant conversion date and (y) with respect to conversions occurring on or after the final regular record date preceding the maturity date, on the maturity date; or



•

if we elect cash settlement or combination settlement, the third business day immediately following the last VWAP trading day of the relevant observation period.

              We will deliver cash in lieu of any fractional share of common stock issuable upon conversion based on:

•

the daily VWAP on the relevant conversion date, in the case of physical settlement; or



•

the daily VWAP on the last VWAP trading day of the relevant observation period, in the case of combination settlement.

              Each conversion will be deemed to have been effected as to any notes surrendered for conversion on the applicable conversion date; provided , however , that the person in whose name any shares of our common stock shall be issuable upon such conversion will be treated as the holder of record of such shares as of the close of business on the conversion date, in the case of physical settlement, or the last VWAP trading day of the relevant observation period, in the case of combination settlement.

Conversion Rate Adjustments

              We will adjust the conversion rate for the following events. However, we will not make any adjustments to the conversion rate if as a result of holding the notes you will otherwise participate (other than in the case of a share split or share combination), at the same time and upon the same terms as holders of our common stock in any of the transactions described below without having to convert their notes as if you held a number of shares of our common stock equal to the applicable conversion rate for each $1,000 principal amount of notes held by you (calculated on an aggregate basis per holder).

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              (1)   If we issue shares of our common stock to all or substantially all holders of our common stock as a dividend or distribution on shares of our common stock, or if we effect a share split or share combination, the conversion rate will be adjusted based on the following formula:

              Any adjustment made under this clause (1) shall become effective immediately after the open of business on the ex-dividend date for such dividend or distribution, or immediately after the open of business on the effective date for such share split or share combination, as applicable. If any dividend or distribution of the type described in this clause (1) is declared but not so paid or made, the conversion rate shall be immediately readjusted, effective as of the date our board of directors or a committee thereof determines not to pay such dividend or distribution, to the conversion rate that would then be in effect if such dividend or distribution had not been declared.

              "Effective date" means the first date on which the shares of our common stock trade on the relevant stock exchange, regular way, reflecting the relevant share split or share combination, as applicable.

              (2)   If we issue to all or substantially all holders of our common stock any rights, options or warrants (other than pursuant to a stockholders rights plan) entitling them to purchase, for a period of 45 calendar days or less from the announcement date for such distribution, shares of our common stock at a price per share that is less than the average of the closing sale prices of our common stock for the ten consecutive trading day period ending on, and including, the trading day immediately preceding the

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announcement date for such issuance, the conversion rate will be increased based on the following formula:

              Any increase made under this clause (2) will be made successively whenever any such rights, options or warrants are issued and shall become effective immediately after the open of business on the ex-dividend date for such issuance. To the extent that such rights, options or warrants are not exercised prior to their expiration or shares of our common stock are not delivered upon exercise of such rights, options or warrants, the conversion rate shall be readjusted to the conversion rate that would then be in effect had the increase with respect to the issuance of such rights, options or warrants been made on the basis of delivery of only the number of shares of common stock actually delivered. If such rights, options or warrants are not so issued, or if such rights, options or warrants are not so exercised prior to their expiration, the conversion rate shall be decreased to the conversion rate that would then be in effect if such ex-dividend date for such issuance had not occurred.

              In determining whether any rights, options or warrants entitle the holders of our common stock to subscribe for or purchase shares of our common stock at less than such average of the closing sale prices for the ten consecutive trading day period ending on, and including, the trading day immediately preceding the announcement date for such issuance, and in determining the aggregate offering price of such shares of our common stock, there shall be taken into account any consideration received by us for such rights, options or warrants and any amount payable on exercise or conversion thereof, the value of such consideration (if other than cash) to be determined by our board of directors or a committee thereof.

              (3)   If we distribute shares of our capital stock, evidences of our indebtedness, other assets or property of ours or rights, options or warrants to acquire our capital stock or other securities, to all or substantially all holders of our common stock, excluding:

•

dividends, distributions or issuances as to which an adjustment was effected pursuant to clause (1) or (2) above;



•

rights issued under a stockholders rights plan;



•

dividends or distributions paid exclusively in cash as to which the provisions set forth in clause (4) below shall apply;

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•

distributions of reference property in a transaction described in "—Change in the Conversion Rights Upon Certain Reclassifications, Business Combinations, Asset Sales and Corporate Events"; and



•

spin-offs described below in the second paragraph of this clause (3),

then the conversion rate will be increased based on the following formula:

              Any increase made under the portion of this clause (3) above will become effective immediately after the open of business on the ex-dividend date for such distribution. If such distribution is not so paid or made, the conversion rate shall be decreased to be the conversion rate that would then be in effect if such distribution had not been declared.

              Notwithstanding the foregoing, if "FMV" (as defined above) is equal to or greater than "SP ₀ " (as defined above), in lieu of the foregoing increase, each holder of a note shall receive, in respect of each $1,000 principal amount thereof, at the same time and upon the same terms as holders of our common stock, the amount and kind of our capital stock, evidences of our indebtedness, other assets or property of ours or rights, options or warrants to acquire our capital stock or other securities that such holder would have received if such holder owned a number of shares of common stock equal to the conversion rate in effect on the ex-dividend date for the distribution.

              With respect to an adjustment pursuant to this clause (3) where there has been a payment of a dividend or other distribution on our common stock in shares of capital stock of any class or series, or similar equity interest, of or relating to a subsidiary or other business unit that are, or, when issued will be, listed or admitted for trading on a U.S. national securities exchange, which is referred to in this

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prospectus supplement as a "spin-off," the conversion rate will be increased based on the following formula:

              Any adjustment to the conversion rate under the preceding paragraph of this clause (3) will be made immediately after the open of business on the day after the last day of the valuation period, but will be given effect as of the open of business on the ex-dividend date for the spin-off. Because we will make the adjustment to the conversion rate at the end of the valuation period with retroactive effect, notwithstanding anything to the contrary, (i) if the settlement date for a note whose conversion is to be settled pursuant to cash settlement or combination settlement occurs on or before the last trading day in the valuation period for any spin-off and any VWAP trading day in the observation period for such conversion occurs on any trading day within such valuation period, then, solely for purposes of determining the consideration due in respect of such conversion, such valuation period will be deemed to be the period from, and including, the ex-dividend date for such spin-off to, and including, the last VWAP trading day in such observation period (or, if such VWAP trading day is not a trading day, the immediately preceding trading day); and (ii) if the settlement date for a note whose conversion is to be settled pursuant to physical settlement occurs on or before the last trading day in the valuation period for a spin-off and the conversion date for such conversion occurs on any trading day within such valuation period, then, solely for purposes of determining the consideration due in respect of such conversion, such valuation period will be deemed to be the period from, and including, the ex-dividend date for such spin-off to, and including, such conversion date (or, if such conversion date is not a trading day, the immediately preceding trading day).

              (4)   If we pay any cash dividends or distributions paid exclusively in cash to all or substantially all holders of our common stock (other than dividends or distributions made in connection with our liquidation, dissolution or winding-up or upon a merger, consolidation or sale, lease, transfer, conveyance or other disposition resulting in a change in the conversion consideration as described under "—Change in the Conversion Rights Upon Certain Reclassifications, Business Combinations,

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Asset Sales and Corporate Events"), the conversion rate will be increased based on the following formula:

              Notwithstanding the foregoing, if "C" (as defined above) is equal to or greater than "SP ₀ " (as defined above), in lieu of the foregoing increase, each holder of a note shall receive, in respect of each $1,000 principal amount thereof, at the same time and upon the same terms as holders of shares of our common stock, the amount of cash that such holder would have received as if such holder owned a number of shares of our common stock equal to the conversion rate in effect on the ex-dividend date for such cash dividend or distribution. To the extent such dividend or distribution is declared but not made or paid, the conversion rate will be readjusted to the conversion rate that would then be in effect had the adjustment been made on the basis of only the dividend or distribution, if any, actually made or paid.

              Any increase made under this clause (4) shall become effective immediately after the open of business on the ex-dividend date for such cash dividend or distribution.

              (5)   If we or any of our subsidiaries make a payment in respect of a tender offer or exchange offer for our common stock, to the extent that the cash and value of any other consideration included in the payment per share of our common stock exceeds the closing sale price of our common stock on the trading day next succeeding the last date on which tenders or exchanges may be made pursuant to

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such tender or exchange offer (the "expiration date"), the conversion rate will be increased based on the following formula:

              Any adjustment to the conversion rate under this clause (5) will be made immediately prior to the open of business on the day following the last day of the averaging period, but will be given effect as of the open of business on the trading day immediately following the expiration date. Because we will make the adjustment to the conversion rate at the end of the averaging period with retroactive effect, notwithstanding anything to the contrary, (i) if the settlement date for a note whose conversion is to be settled pursuant to cash settlement or combination settlement occurs on or before the last trading day in the averaging period for such tender or exchange offer and any VWAP trading day in the observation period for such conversion occurs on any trading day within such averaging period, then, solely for purposes of determining the consideration due in respect of such conversion, such averaging period will be deemed to be the period from, and including, the trading day immediately after the expiration date for such tender or exchange offer to, and including, the last VWAP trading day in such observation period (or, if such VWAP trading day is not a trading day, the immediately preceding trading day); and (ii) if the settlement date for a note whose conversion is to be settled pursuant to physical settlement occurs on or before the last trading day in the averaging period for such tender or exchange offer and the conversion date for such conversion occurs on any trading day within such averaging period, then, solely for purposes of determining the consideration due in respect of such conversion, such averaging period will be deemed to be the period from, and including, the trading day immediately after the expiration date to, and including, such conversion date (or, if such conversion date is not a trading day, the immediately preceding trading day).

              To the extent that any stockholder's rights plan adopted by us is in effect upon conversion of the notes, you will receive, in addition to any common stock due upon conversion, the rights under the applicable rights agreement. However, if, prior to any conversion, the rights have separated from the shares of common stock in accordance with the provisions of the applicable rights plan, the conversion rate will be adjusted at the time of separation as if we distributed to all or substantially all holders of

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our common stock, shares of our capital stock, evidences of indebtedness, assets, property, rights, options or warrants as described above in clause (3), subject to readjustment in the event of the expiration, termination or redemption of such rights. For the avoidance of doubt, any issuance of stockholder rights (including pursuant to a stockholder rights plan adopted after the date of initial issuance of the initial notes) will not cause an adjustment of the conversion rate unless and until such stockholder rights have separated from the common stock.

              Notwithstanding the foregoing, if a conversion rate adjustment becomes effective on any ex-dividend date as described above, and a holder that has converted its notes on or after such ex-dividend date and on or prior to the related record date would be treated as the record holder of shares of our common stock as of the related conversion date as described under "—Settlement Upon Conversion" based on an adjusted conversion rate for such ex-dividend date, then, notwithstanding the foregoing conversion rate adjustment provisions, the conversion rate adjustment relating to such ex-dividend date will not be made for such converting holder. Instead, such holder will be treated as if such holder were the record owner of the shares of our common stock on an unadjusted basis and participate in the related dividend, distribution or other event giving rise to such adjustment.

              Notwithstanding the foregoing, if a holder converts a note, combination settlement is applicable to such note and the daily settlement amount for any VWAP trading day during the observation period applicable to such note:

•

is calculated based on a conversion rate adjusted on account of any event described in clauses (1) through (5) above; and



•

includes any shares of our common stock that entitle their holder to participate in such event;

then, notwithstanding the foregoing conversion rate adjustment provisions, such conversion rate adjustment will not be made for such converting holder for such trading day. Instead, such holder will be treated as if such holder were the record owner of the shares of our common stock on an unadjusted basis and participate in the related dividend, distribution or other event giving rise to such adjustment.

              If we issue rights, options or warrants that are only exercisable upon the occurrence of certain triggering events, then:

•

we will not adjust the conversion rate pursuant to the clauses above until the earliest of these triggering events occurs; and



•

we will readjust the conversion rate to the extent any of these rights, options or warrants are not exercised before they expire;

provided that the rights, options or warrants trade together with our common stock and will be issued in respect of future issuances of the shares of our common stock.

              To the extent permitted by applicable law and subject to the applicable rules of the NASDAQ Capital Market, we (a) are permitted to increase the conversion rate of the notes by any amount for a period of at least 20 business days if we determine that such increase would be in our best interest and (b) may also (but are not required to) increase the conversion rate of the notes to avoid or diminish income tax to holders of our common stock or rights to purchase shares of our common stock in connection with a dividend or distribution of shares (or rights to acquire shares) or similar event.

              If we adjust the conversion rate pursuant to the above provisions, we will deliver a notice to the trustee, conversion agent (if other than the trustee) and record holders of the notes containing the relevant information.

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              Except as described above and under "—Adjustment to Conversion Rate Upon a Make-Whole Fundamental Change" below, the conversion rate will not be adjusted. Without limiting the foregoing, the conversion rate will not be adjusted:

•

except as described above, upon the sale of shares of our common stock for a purchase price that is less than the market price per share of our common stock or less than the conversion price;



•

upon the issuance of any shares of our common stock pursuant to any present or future plan providing for the reinvestment of dividends or interest payable on our securities and the investment of additional optional amounts in shares of our common stock under any plan;



•

upon the issuance of any shares of our common stock or options or rights to purchase those shares pursuant to any present or future employee, director or consultant benefit plan or program of or assumed by us or any of our subsidiaries;



•

upon the issuance of any shares of our common stock pursuant to any option, warrant, right or exercisable, exchangeable or convertible security not described in the preceding bullet and outstanding as of the date the initial notes were first issued;



•

for the repurchase of any shares of our common stock that is not a tender offer or exchange offer of the nature described in clause (5) above, including, but not limited to, pursuant to an open-market share repurchase program, a structured or derivative transaction or other buyback transaction;



•

solely for a change in the par value of the common stock; or



•

for accrued and unpaid interest, if any.

              In the event of a taxable distribution to holders of our common stock which results in an adjustment of the conversion rate, a holder of the notes may, in certain circumstances (such as a distribution of a cash dividend), be deemed to have received a distribution subject to U.S. federal income tax as a dividend. In certain other circumstances, the absence of such an adjustment may result in a taxable dividend to the holders of our common stock. For a discussion of the U.S. federal income tax treatment of an adjustment to the conversion rate, see "Material U.S. Federal Income Tax Considerations."

              We will not adjust the conversion rate pursuant to the clauses above unless the adjustment would result in a change of at least 1% in the then-effective conversion rate. However, we will carry forward any adjustment that we would otherwise have to make and take that adjustment into account in any subsequent adjustment. Notwithstanding the foregoing, all such carried-forward adjustments shall be made with respect to the notes (i) in connection with any subsequent adjustment to the conversion rate of at least 1% and (ii)(a) on each trading day of any observation period related to the conversion of the notes (in the case of cash settlement or combination settlement) or (b) on the conversion date for any notes (in the case of physical settlement).

              Adjustments to the conversion rate will be calculated to the nearest 1/10,000th of a share.

Change in the Conversion Rights Upon Certain Reclassifications, Business Combinations, Asset Sales and Corporate Events

              If we:

•

reclassify or change our common stock (other than changes in par value or from no par value resulting from a subdivision or combination), or

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•

consolidate or merge with or into or enter into a binding share exchange with any person or sell, lease, transfer, convey or otherwise dispose of all or substantially all of our property and assets and the property and assets of our subsidiaries taken as a whole to another person,

and, in either case, holders of our common stock receive stock, other securities or other property or assets (including cash or any combination thereof) with respect to or in exchange for their common stock, then from and after the effective date of such transaction, the right to convert each outstanding $1,000 principal amount of notes based on our common stock will, without the consent of any holders of the notes, be changed into a right to convert each such note based on the kind and amount of stock, other securities or other property or assets (including cash or any combination thereof) (the "reference property") that a holder of a number of shares of common stock equal to the conversion rate immediately prior to such transaction would have been entitled to receive upon such transaction. We or the successor or purchasing corporation, as the case may be, will execute with the trustee, without the consent of the holders, a supplemental indenture providing that, at and after the effective date of the transaction, the right to convert each outstanding $1,000 principal amount of notes will be changed into a right to convert such principal amount of notes into the kind and amount of reference property that a holder of a number of shares of common stock equal to the conversion rate immediately prior to such transaction would have been entitled to receive upon such transaction. If the transaction causes our common stock to be converted into or exchanged for the right to receive more than a single type of consideration (determined based in part upon any form of stockholder election), the reference property into which the notes will become convertible will be deemed to be based on the weighted average of the kind and amount of consideration actually received by holders of a majority of our common stock that voted for such an election (if electing between two types of consideration) or holders of a plurality of our common stock that voted for such an election (if electing between more than two types of consideration), as the case may be, and if no holders of our common stock affirmatively make such an election, the types and amounts of consideration actually received by the holders of our common stock. In all cases the provisions above under "—Settlement Upon Conversion" relating to the satisfaction of our conversion obligation shall continue to apply with respect to the calculation of the consideration due upon conversion, with the daily conversion value, daily settlement amount and the daily VWAPs determined based on a unit of reference property that a holder of one share of our common stock would have received in such transaction; provided , however , that if the holders of our common stock receive only cash in such transaction, the consideration due upon conversion shall equal the conversion rate in effect on the conversion date, multiplied by the price paid per share of common stock in such transaction, and settlement of any conversion thereafter will occur on the third business day following the applicable conversion date. We may not become a party to any such transaction unless its terms are consistent with the foregoing.

Adjustment to Conversion Rate Upon a Make-Whole Fundamental Change

              If the "effective date" (as defined below) of a "fundamental change" (as defined below and determined after giving effect to any exceptions to or exclusions from such definition, but without regard to the proviso in clause (2) of the definition thereof, a "make-whole fundamental change") occurs prior to the maturity date of the notes and a holder elects to convert its notes in connection with such make-whole fundamental change, we will increase the conversion rate as described below. The number of additional shares by which the conversion is increased (the "additional shares") will be determined by reference to the table below, based on the date on which the make-whole fundamental change becomes effective (the "effective date") and the price (the "stock price") paid (or deemed paid) per share for our common stock in such make-whole fundamental change. If holders of our common stock receive only cash in such transaction, the price paid (or deemed paid) per share will be the cash amount paid per share. Otherwise, the price paid (or deemed paid) per share will be the average of the closing sale prices of our common stock over the five trading day period ending on, and

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including, the trading day immediately preceding the effective date of such make-whole fundamental change.

              We will notify you, the trustee and conversion agent (if other than the trustee) of the effective date of any make-whole fundamental change no later than one business day after such effective date.

              A conversion of the notes by a holder will be deemed for these purposes to be "in connection with" a make-whole fundamental change if the conversion notice is received by the conversion agent on or after the effective date of the make-whole fundamental change but before the close of business on the second business day immediately preceding the related fundamental change repurchase date (or, in the case of a make-whole fundamental change that would have been a fundamental change but for the proviso in clause (2) of the definition thereof, the 35th trading day immediately following the effective date of such make-whole fundamental change) as specified in the repurchase notice described under "—Fundamental Change Put."

              The number of additional shares will be adjusted in the same manner and at the same time as the conversion rate of the notes is adjusted as described above under "—Conversion Rate Adjustments." The stock prices set forth in the first row of the table below (i.e., the column headers) will be simultaneously adjusted to equal the stock prices immediately prior to such adjustment, multiplied by a fraction, the numerator of which is the conversion rate immediately prior to the adjustment and the denominator of which is the conversion rate as so adjusted.

              The following table sets forth the number of additional shares per $1,000 principal amount of notes by which the conversion rate shall be increased upon conversion in connection with a make-whole fundamental change:

              The exact stock price and effective date may not be set forth in the table above, in which case, if the stock price is:

•

between two stock prices in the table or the effective date is between two effective dates in the table, the number of additional shares by which the conversion rate will be increased will be determined by a straight-line interpolation between the number of additional shares set forth for the higher and lower stock prices and the earlier and later effective dates based on a 360-day year;



•

greater than $325.00 per share (subject to adjustment in the same manner and at the same time as the stock prices in the table above), we will not increase the conversion rate;



•

less than $55.06 per share (subject to adjustment in the same manner and at the same time as the stock prices in the table above), we will not increase the conversion rate.

              Notwithstanding the foregoing, in no event will the total number of shares of our common stock issuable upon conversion exceed 18.1620 shares per $1,000 principal amount of notes, subject to adjustment in the same manner and at the same time as the conversion rate.

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              Our obligation to increase the conversion rate for notes converted in connection with a fundamental change could be considered a penalty, in which case the enforceability thereof would be subject to general principles of reasonableness and equitable remedies.

              In the event of a conversion of notes in connection with a make-whole fundamental change that results in an adjustment of the conversion rate, a holder of notes may be deemed to have received a distribution subject to U.S. federal income tax as a dividend. See "Material U.S. Federal Income Tax Considerations."

Adjustments of Prices

              Whenever any provision of the indenture requires us to calculate the closing sale prices, the daily VWAPs, the daily conversion values or the daily settlement amounts over, or based on, a span of multiple days (including an observation period and the "stock price" for purposes of a make-whole fundamental change), we will make appropriate adjustments to each to account for any adjustment to the conversion rate that becomes effective, or any event requiring an adjustment to the conversion rate where the ex-dividend date of the event occurs, at any time during the period when the closing sale prices, the daily VWAPs, the daily conversion values or the daily settlement amounts are to be calculated.

              For the avoidance of doubt, the adjustments made pursuant to the foregoing paragraph will be made, solely to the extent we determine in our good faith judgment that any such adjustment is necessary, without duplication of any adjustment made pursuant to the provision set forth under "—Conversion Rate Adjustments."

Fundamental Change Put

              If a fundamental change (as defined below) occurs at any time prior to the maturity of the notes, you will have the right to require us to repurchase on the fundamental change repurchase date, at the fundamental change repurchase price described below, all or part of your notes for which you have properly delivered and not withdrawn a written repurchase notice. The notes submitted for repurchase must be $1,000 in principal amount or whole multiples of $1,000 in excess thereof.

              The fundamental change repurchase price will be payable in cash and will equal 100% of the principal amount of the notes being repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. However, if the fundamental change repurchase date is after a record date and on or prior to the corresponding interest payment date, the full amount of interest due will be paid on the interest payment date to the holder of record on the record date and the fundamental change repurchase price will be equal to 100% of the principal amount of notes to be repurchased.

              A "fundamental change" will be deemed to have occurred when any of the following has occurred:

(1)

a "person" or "group," other than us and our wholly owned subsidiaries files a Schedule TO or any schedule, form or report under the Exchange Act disclosing that such person or group has become the "beneficial owner" (as these terms are defined in Rule 13d-3 and Rule 13d-5 under the Exchange Act), directly or indirectly, of more than 50% of our capital stock that is at the time entitled to vote by the holder thereof in the election of our board of directors (or comparable body);



(2)

the consummation of (A) any recapitalization, reclassification or change of our common stock (other than changes resulting from a subdivision or combination) as a result of which our common stock would be converted into, or exchanged for, stock, other securities, other property or assets; (B) any share exchange, consolidation or

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merger of us pursuant to which our common stock will be converted into cash, securities or other property or assets (or any combination thereof); or (C) any sale, lease or other transfer in one transaction or a series of transactions of all or substantially all of the consolidated assets of us and our subsidiaries, taken as a whole, to any person other than one of our wholly owned subsidiaries; provided , however , that neither (a) a transaction described in clause (B) in which the holders of all classes of our common equity immediately prior to such transaction own, directly or indirectly, more than 50% of all classes of common equity of the continuing or surviving corporation or transferee or the parent thereof immediately after such transaction in substantially the same proportions as such ownership immediately prior to such transaction nor (b) any reorganization or merger of us solely for the purpose of changing our jurisdiction of incorporation that results in a reclassification, conversion or exchange of outstanding shares of common stock solely into shares of common stock of the surviving entity shall be a fundamental change pursuant to this clause (2);

(3)

the adoption of a plan relating to our liquidation or dissolution; or



(4)

our common stock or other shares of capital stock or reference property into which the notes are convertible is neither listed for trading on The New York Stock Exchange, the NASDAQ Capital Market, the NASDAQ Global Market or the NASDAQ Global Select Market (or any of their respective successors).

              Notwithstanding the foregoing, any transaction or event described above will not constitute a fundamental change if, in connection with such transaction or event, or as a result therefrom, a transaction described in clause (1) or (2) above occurs and at least 90% of the consideration paid for our common stock (excluding cash payments for fractional shares and cash payments made pursuant to dissenters' appraisal rights) consists of shares of common stock traded on any of the New York Stock Exchange, the NASDAQ Capital Market, the NASDAQ Global Market or the NASDAQ Global Select Market (or any of their respective successors) (or will be so traded or quoted immediately following the completion of the merger or consolidation or such other transaction) and, as a result of such transaction, the notes become convertible into a combination of cash (in respect of an amount up to, and including, the principal portion of such notes) and reference property comprised of such consideration as described under "—Conversion Rate Adjustments—Change in the Conversion Rights Upon Certain Reclassifications, Business Combinations, Asset Sales and Corporate Events" above.

              On or before the tenth business day after the occurrence of a fundamental change, we will provide to all record holders of the notes on the date of the fundamental change at their addresses shown in the register of the registrar and to beneficial owners to the extent required by applicable law, the trustee and the paying agent appointed in connection with the fundamental change, a written notice of the occurrence of the fundamental change and the resulting repurchase right. Such notice shall state, among other things, the event causing the fundamental change and the procedures you must follow to require us to repurchase your notes.

              The fundamental change repurchase date will be a date specified by us in the notice of a fundamental change that is not less than 20 nor more than 35 business days after the date of the notice of a fundamental change. The fundamental change repurchase date shall be subject to postponement in order to allow us to comply with applicable law as a result of changes to such applicable law occurring after the date of the indenture.

              To exercise your repurchase right, you must deliver, prior to the close of business on the business day immediately preceding the fundamental change repurchase date, a written notice to the

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paying agent of your exercise of your repurchase right (together with the notes to be repurchased, if certificated notes have been issued). The repurchase notice must state:

•

the portion of the principal amount of the notes to be repurchased, which must be $1,000 or whole multiples of $1,000 in excess thereof; and



•

that the notes are to be repurchased by us pursuant to the applicable provisions of the notes and the indenture.

              In addition, if you hold a beneficial interest in a global note, your repurchase notice must comply with appropriate DTC procedures and if you hold certificated notes, your repurchase notice must identify the relevant notes certificate numbers.

              You may withdraw your repurchase notice at any time prior to the close of business on the business day immediately preceding the fundamental change repurchase date by delivering a written notice of withdrawal to the paying agent. If a repurchase notice is given and withdrawn during that period, we will not be obligated to repurchase the notes listed in the repurchase notice. The withdrawal notice must state:

•

the principal amount of the withdrawn notes (which must be $1,000 or an integral multiple thereof); and



•

the principal amount, if any (which must be $1,000 or an integral multiple thereof), which remains subject to the repurchase notice.

              In addition, if you hold a beneficial interest in a global note, your withdrawal notice must comply with appropriate DTC procedures and if you hold certificated notes, your withdrawal notice must identify the certificate numbers of the withdrawn notes.

              Payment of the fundamental change repurchase price for notes for which a repurchase notice has been delivered and not withdrawn is conditioned upon book-entry transfer or delivery of the notes, together with necessary endorsements, to the paying agent, as the case may be. Payment of the fundamental change repurchase price for the notes will be made promptly following the later of the fundamental change repurchase date and the time of book-entry transfer or delivery of the notes, as the case may be.

              If the paying agent holds on the fundamental change repurchase date cash sufficient to pay the fundamental change repurchase price of the notes that holders have elected to require us to repurchase, then, as of the fundamental change repurchase date:

•

the notes will cease to be outstanding and interest will cease to accrue, whether or not book-entry transfer of the notes has been made or the notes have been delivered to the paying agent, as the case may be; and



•

all other rights of the holders of notes will terminate, other than the right to receive the fundamental change repurchase price upon delivery or transfer of the notes.

              In connection with any repurchase, we will, to the extent applicable:

•

comply with the provisions of Rule 13e-4 and any other tender offer rules under the Exchange Act that may be applicable at the time of the offer to repurchase the notes;



•

file a Schedule TO or any other schedule required in connection with any offer by us to repurchase the notes; and



•

comply with all other federal and state securities laws in connection with any offer by us to repurchase the notes.

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              No notes may be repurchased at your option upon a fundamental change if the principal amount of the notes has been accelerated, and such acceleration has not been rescinded, on or prior to the fundamental change repurchase date (except in the case of an acceleration resulting from a default by us in the payment of the fundamental change repurchase price with respect to such notes).

              Notwithstanding the foregoing, we will not be required to purchase, or to make an offer to purchase, the notes upon a fundamental change if a third party makes such an offer in the same manner, at the same time and otherwise in compliance with the requirements for an offer made by us as set forth above and such third party purchases all notes properly surrendered and not validly withdrawn under its offer in the same manner, at the same time and otherwise in compliance with the requirements for an offer made by us as set forth above.

              Notwithstanding the foregoing, we will not be required to give such notice or repurchase the notes as described above upon a fundamental change pursuant to clause (2) of the definition thereof if (1) such fundamental change results in the notes becoming convertible (pursuant to the provisions described above under "—Change in the Conversion Rights Upon Certain Reclassifications, Business Combinations, Asset Sales and Corporate Events") into an amount of cash per note greater than the fundamental change purchase price (assuming the maximum amount of accrued interest would be payable based on the latest possible fundamental change repurchase date) and (2) we provide timely notice of the holders' right to convert their notes based on such fundamental change as described above under "—Conversion Rights—Conversion Upon Specified Corporate Transactions."

              The definition of "fundamental change" includes a phrase relating to the sale, lease, transfer, conveyance or other disposition, in one or a series of related transactions, of all or substantially all of our assets and those of our subsidiaries taken as a whole. There is no precise, established definition of the phrase "substantially all" under applicable law. Accordingly, the ability of a holder of notes to require us to repurchase the notes as a result of a sale, lease, transfer, conveyance or other disposition of less than all of our assets and those of our subsidiaries taken as a whole to another person or group may be uncertain.

              We may be unable to repurchase your notes in cash upon a fundamental change. Our ability to repurchase the notes with cash in the future may be limited by the terms of our then-existing borrowing agreements or otherwise. In addition, the occurrence of a fundamental change could cause an event of default under the terms of our then-existing borrowing agreements. We cannot assure you that we would have the financial resources, or would be able to arrange financing, to pay the fundamental change repurchase price in cash.

              This fundamental change repurchase right could discourage a potential acquirer of the Company. However, this fundamental change repurchase feature is not the result of management's knowledge of any specific effort to obtain control of us by means of a merger, tender offer, solicitation or otherwise, or part of a plan by management to adopt a series of anti-takeover provisions.

              Our obligation to repurchase the notes upon a fundamental change would not necessarily afford you protection in the event of a highly leveraged or other transaction involving us that may adversely affect holders. We also could, in the future, enter into certain transactions, including certain recapitalizations, that would not constitute a fundamental change but would increase the amount of our (or our subsidiaries') outstanding debt. The incurrence of significant amounts of additional debt could adversely affect our ability to service our then existing debt, including the notes.

Consolidation, Merger and Sale of Assets

              The indenture provides that we may not, in a single transaction or a series of related transactions, consolidate with or merge with or into any other person or sell, convey, transfer, lease or

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otherwise dispose of all or substantially all of the property and assets of the Company and its subsidiaries taken as a whole to another person, unless:

•

either (a) we are the continuing corporation or (b) the resulting, surviving or transferee person (if other than us) is a corporation organized and existing under the laws of the United States, any state thereof or the District of Columbia and such person assumes, by a supplemental indenture, all of our obligations under the notes and the indenture;



•

immediately after giving effect to such transaction, no default or event of default has occurred and is continuing; and



•

we have delivered to the trustee certain certificates and opinions of counsel to the extent required by the indenture.

              In the event of any transaction described in and complying with the conditions listed in the immediately preceding paragraph in which the Company is not the continuing corporation, the successor person formed or remaining shall succeed, and be substituted for, and may exercise every right and power of, the Company, and the Company shall be discharged from its obligations, under the notes and the indenture, except in the case of a lease.

              This covenant includes a phrase relating to the sale, conveyance, transfer, lease and other disposition of "all or substantially all" of the property and assets of the Company and its subsidiaries. There is no precise, established definition of the phrase "all or substantially all" under applicable law. Accordingly, whether a sale, conveyance, transfer, lease or other disposition of less than all of the property and assets of the Company and its subsidiaries constitutes a sale or other disposition of "all or substantially all" may be uncertain.

              An assumption by any person of the Company's obligations under the notes and the indenture might be deemed for U.S. federal income tax purposes to be a taxable exchange of the notes for new notes by the holders thereof, resulting in recognition of gain or loss for such purposes and possibly other adverse tax consequences to the holders. Holders should consult their own tax advisors regarding the tax consequences of such an assumption.

Events of Default; Notice and Waiver

              The following will be events of default under the indenture:

•

we fail to pay any interest on the notes when due and such failure continues for a period of 30 calendar days;



•

we fail to pay principal of the notes when due at maturity, or we fail to pay the fundamental change repurchase price payable, in respect of any notes when due;



•

we fail to comply with our obligation to convert any notes in accordance with the indenture, and such failure continues for five business days following the scheduled settlement date for such conversion;



•

we fail to comply with the covenant set forth above under "—Consolidation, Merger and Sale of Assets;"



•

we fail to provide notice of any transaction described above under "—Conversion Rights—Conversion Upon Specified Corporate Transactions";



•

we fail to provide notice of a fundamental change when due as required by the indenture;



•

we fail to perform or observe any other term, covenant or agreement in the notes or the indenture for a period of 60 consecutive calendar days after written notice of such failure is

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given to us by the trustee or to us and the trustee by the holders of at least 25% in aggregate principal amount of the notes then outstanding;

•

a failure to pay when due (whether at stated maturity or otherwise), or a default that results in the acceleration of maturity, of any indebtedness for borrowed money of the Company or any of its subsidiaries in an aggregate amount in excess of $50.0 million (or its foreign currency equivalent), unless such indebtedness is paid or discharged, or such acceleration is rescinded, stayed or annulled, within a period of 30 calendar days after written notice of such failure is given to us by the trustee or to us and the trustee by the holders of at least 25% in aggregate principal amount of the notes then outstanding;



•

a final judgment for the payment in excess of $50.0 million (excluding any amounts covered by insurance) rendered against the Company or any of its subsidiaries, which judgment is not paid, discharged, bonded, waived or stayed within 60 calendar days after (i) the date on which the right to appeal or petition for review thereof has expired if no such appeal or review has commenced, or (ii) the date on which all rights to appeal or petition for review have been extinguished; or



•

certain events involving our bankruptcy, insolvency or reorganization or the bankruptcy, insolvency or reorganization of the Company or any of its significant subsidiaries (as defined below).

              A "significant subsidiary" is a subsidiary that is a "significant subsidiary" as defined under Rule 1-02(w) of Regulation S-X; provided that, in the case of a subsidiary that meets the criteria of clause (3) of the definition thereof but not clause (1) or (2) thereof, such subsidiary shall not be deemed to be a significant subsidiary unless the subsidiary's income from continuing operations before income taxes, extraordinary items and cumulative effect of a change in accounting principle, exclusive of amounts attributable to any non-controlling interests, for the last completed fiscal year prior to the date of such determination exceeds $25,000,000.

              We are required to notify the trustee promptly upon becoming aware (and in no event later than 10 calendar days after we become aware) of the occurrence of any default or event of default under the indenture known to us. The trustee is required within 90 calendar days of obtaining actual knowledge of the occurrence of any event of default to give to the registered holders of the notes notice of the occurrence and continuation of an event of default known to it. However, the trustee may withhold notice to the holders of the notes of any events of default, except events of default in payment of principal or interest on the notes or defaults in the failure to deliver the consideration due upon conversion, if the trustee, in good faith, determines that the withholding of such notice is in the interests of the holders. We are also required to deliver to the trustee, on or before a date not more than 120 calendar days after the end of each fiscal year, a written statement as to compliance with the indenture, including whether or not any default has occurred.

              If an event of default specified in the last bullet point listed above occurs and continues with respect to us (and not involving solely one or more of our significant subsidiaries), the principal amount of the notes and accrued and unpaid interest on the outstanding notes will automatically become due and payable. If any other event of default occurs and is continuing, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding notes, by written notice to us, may declare the principal amount of the notes and accrued and unpaid interest on the outstanding notes to be due and payable. Thereupon, the trustee may, in its discretion, proceed to protect and enforce the rights of the holders of the notes by appropriate judicial proceedings.

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              After a declaration of acceleration, but before a judgment or decree for payment of the money due has been obtained by the trustee, the holders of a majority in aggregate principal amount of the notes outstanding, by written notice to us and the trustee, may rescind and annul such declaration if:

•

we have paid (or deposited with the trustee a sum sufficient to pay) (1) all overdue interest on all notes; (2) the principal amount of any notes that have become due otherwise than by such declaration of acceleration; (3) to the extent that payment of such interest is lawful, interest upon overdue interest; and (4) all sums paid or advanced by the trustee under the indenture and the compensation and reasonable expenses, disbursements and advances of the trustee, its agents and counsel; and



•

all events of default, other than the non-payment of the principal amount and any accrued and unpaid interest that have become due solely by such declaration of acceleration or the failure to deliver consideration upon conversion, have been cured or waived.

              The holders of a majority in aggregate principal amount of the outstanding notes will have the right to direct the time, method and place of any proceedings for any remedy available to the trustee or the exercise of any other right or power conferred on the trustee, subject to limitations specified in the indenture.

              If any portion of the amount payable on the notes upon such acceleration thereof as described above is considered by a court to be unearned interest (through the allocation of the value of the instrument to the embedded warrant or otherwise), the court could disallow recovery of any such portion.

              No holder of the notes may pursue any remedy under the indenture, except in the case of a default in the payment of principal or interest on the notes or settlement of our conversion obligation, unless:

•

the holder has given the trustee written notice of an event of default;



•

the holders of at least 25% in aggregate principal amount of the outstanding notes have made a written request to the trustee to pursue the remedy, and offer security or indemnity against any costs, liability or expense of the trustee satisfactory to the trustee;



•

the trustee fails to comply with the request within 60 calendar days after receipt of the request and offer of indemnity; and



•

the trustee has not received an inconsistent direction from the holders of a majority in aggregate principal amount of the outstanding notes.

              Notwithstanding the foregoing, the indenture provides, if we so elect, that the sole remedy for an event of default relating to our failure to comply with the reporting obligations in the indenture, which are described below under the caption "—Reports" below, will, at our option, for the 365 days after the occurrence of such an event of default consist exclusively of the right to receive additional interest on the notes at an annual rate equal to:

•

0.25% of the outstanding principal amount of the notes from the first date of the occurrence of such event of default to, but not including, the 180th day thereafter (or such earlier date on which the event of default relating to the reporting obligations shall have been cured or waived); and



•

0.50% of the outstanding principal amount of the notes from the 180th day after the first date of such occurrence of such event of default to the 365th day thereafter (or such earlier date on which the event of default relating to the reporting obligations shall have been cured or waived).

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              The additional interest pursuant to the foregoing provisions will be payable in arrears on each interest payment date following accrual in the same manner as regular interest on the notes. The additional interest will accrue on all outstanding notes from and including the date on which an event of default relating to a failure to comply with the reporting obligations in the indenture first occurs to, but not including, the 366th day thereafter (or such earlier date on which the event of default relating to the reporting obligations shall have been cured or waived). On such 366th day (or earlier, if the event of default relating to the reporting obligations is cured or waived prior to such 366th day), if such event of default is continuing, such additional interest will cease to accrue and the notes will be subject to acceleration as provided above. The provisions of the indenture described in this paragraph will not affect the rights of holders of notes in the event of the occurrence of any other event of default. In the event we do not elect to pay the additional interest upon an event of default in accordance with this paragraph or we elected to make such payment but do not pay the additional interest when due, the notes will be immediately subject to acceleration as provided above. In no event shall additional interest payable pursuant to the foregoing election accrue at a rate per year in excess of the applicable rate specified in the preceding paragraph, regardless of the number of events or circumstances giving rise to requirements to pay such additional interest pursuant to this paragraph.

Waiver

              The holders of a majority in aggregate principal amount of the notes outstanding may, on behalf of the holders of all the notes, waive any existing and past default or event of default under the indenture and its consequences, except:

•

our failure to pay principal of or interest on any notes when due;



•

our failure to convert any notes into cash and, if applicable, common stock as required by the indenture;



•

our failure to pay the fundamental change repurchase price on the fundamental change repurchase date in connection with a holder exercising its repurchase rights; or



•

our failure to comply with any of the provisions of the indenture that would require the consent of the holder of each outstanding notes affected.

Modification

Changes Requiring Approval of Each Affected Holder

              The indenture (including the terms and conditions of the notes) may not be modified or amended without the written consent or the affirmative vote (including, without limitation, consents obtained in connection with a purchase of, or tender offer or exchange offer for, notes) of the holder of each note affected by such change to:

•

change the maturity date of any notes;



•

reduce the rate or extend the time for payment of interest on any notes;



•

reduce the principal amount of any notes;



•

reduce any amount payable upon repurchase of any notes upon a fundamental change;



•

impair the right of any holder to receive payment of principal (including the fundamental change repurchase price, if applicable) of, accrued and unpaid interest, if any, on, and the consideration due upon conversion of, its notes on or after the respective due dates expressed or provided for in the indenture or to institute suit for the enforcement of any such payment;

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•

change the currency in which any note is payable;



•

change our obligation to repurchase any notes upon a fundamental change in a manner adverse to the holders;



•

change the ranking of the notes;



•

adversely affect the conversion right of a holder to convert its notes pursuant to the terms of the indenture;



•

subject to specified exceptions, modify certain provisions of the indenture relating to modification of the indenture or waiver under the indenture; or



•

make any change in the modification or amendment provisions that require each holder's consent or in the waiver provisions.

Changes Requiring Majority Approval

              The indenture (including the terms and conditions of the notes) may be modified or amended, except as described above, with the written consent or affirmative vote (including, without limitation, consents obtained in connection with the purchase of, or tender offer or exchange offer for, notes) of the holders of a majority in aggregate principal amount of the notes then outstanding.

Changes Requiring No Approval

              The indenture (including the terms and conditions of the notes) may be modified or amended by us and the trustee, without the consent of the holder of any notes, to, among other things:

•

provide for conversion rights of holders of the notes and our repurchase obligations in connection with a fundamental change in the event of any reclassification of our common stock, merger or consolidation, or sale, conveyance, transfer, lease or other disposition of all or substantially all of the property and assets of the Company and its subsidiaries taken as a whole;



•

secure the notes;



•

provide for the assumption of our obligations to the holders of the notes in the event of a merger or consolidation, or sale, conveyance, transfer, lease or other disposition of all or substantially all of the property and assets of the Company and its subsidiaries taken as a whole;



•

surrender any right or power conferred upon us;



•

add to our covenants or events of default for the benefit of the holders of the notes;



•

entering into supplemental indentures as described above under "—Consolidation, Merger and Sale of Assets;"



•

cure any ambiguity or correct or supplement any inconsistent or otherwise defective provision or omission contained in the indenture; provided that such modification or amendment does not, in the good faith determination of our board of directors or a committee thereof, adversely affect the interests of the holders of the notes in any material respect; provided , further , that any amendment, supplement or other modification made to conform the provisions of the indenture to the description of the notes contained in the prospectus supplement dated January 11, 2018 as supplemented by the related pricing term sheet will not be deemed to adversely affect the interests of the holders of the notes;

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•

in connection with any share exchange event, provide that the notes are convertible into reference property, subject to the provisions described under "Conversion Rights—Settlement Upon Conversion" above, and make certain related changes to the terms of the notes to the extent expressly required by the indenture (as determined in good faith by the board of directors or a committee thereof);



•

increase the conversion rate;



•

comply with the requirements of the SEC in order to effect or maintain the qualification of the indenture under the Trust Indenture Act;



•

comply with the rules of any applicable securities depositary, including DTC;



•

permit or confirm the issuance of additional notes in accordance with the indenture;



•

add guarantees of obligations under the notes;



•

adding or modifying any other provision(s) or omission(s) which we may deem necessary or desirable and which will not adversely affect the interests of the holders of the notes in any material respect, in the good faith determination of our board of directors or a committee thereof; and



•

evidence or provide for a successor trustee, including the appointment thereof.

Other

              The consent of the holders of notes is not necessary under the indenture to approve the particular form of any proposed modification or amendment. It is sufficient if such consent approves the substance of the proposed modification or amendment. After a modification or amendment under the indenture becomes effective, we are required to send to the holders a notice briefly describing such modification or amendment. However, the failure to give such notice to all the holders, or any defect in the notice, will not impair or affect the validity of the modification or amendment.

Notes Not Entitled to Consent

              Any notes held by us or by any person directly or indirectly controlling or controlled by or under direct or indirect common control with us shall be disregarded (from both the numerator and the denominator) for purposes of determining whether the holders of the requisite aggregate principal amount of the outstanding notes have consented to a modification, amendment or waiver of the terms of the indenture.

Discharge

              We may satisfy and discharge our obligations under the indenture by delivering to the securities registrar for cancellation all outstanding notes or by irrevocably depositing with the trustee or delivering to the holders, as applicable, after all of the notes have (i) become due and payable, whether at maturity or at any fundamental change repurchase date, and/or (ii) been converted (and the related consideration due upon conversion has been determined), cash or cash and/or shares of common stock (solely to satisfy outstanding conversions), as applicable, sufficient to pay all of the outstanding notes and/or satisfy all conversions, as the case may be, and pay all other sums payable under the indenture by us. Such discharge is subject to terms contained in the indenture.

Repurchase and Cancellation

              We may, to the extent permitted by law, repurchase any notes in the open market or by tender offer at any price or by private agreement. Any notes repurchased by us may, at our option, be

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surrendered to the trustee for cancellation, but may not be reissued or resold by us. Any notes surrendered for cancellation may not be reissued or resold and will be promptly cancelled (other than notes purchased pursuant to cash-settled swaps or other derivatives).

Reports

              The indenture provides that any documents or reports that we are required to file with the SEC pursuant to Section 13 or 15(d) of the Exchange Act must be filed by us with the trustee within 15 days after the same are required to be filed with the SEC (giving effect to any grace period provided by Rule 12b-25 or any successor rule under the Exchange Act). Documents filed by us with the SEC via the EDGAR system (or any successor thereto) will be deemed to be filed with the trustee as of the time such documents are filed via EDGAR (or such successor). The trustee shall have no obligation to determine if and when the Company's statements or reports are publicly available and/or accessible electronically. Notwithstanding anything to the contrary, we shall in no event be required to file with, or otherwise provide or disclose to, the trustee or any holder any information for which we are seeking, or have received, confidential treatment from the SEC.

              Delivery of the reports and documents delivered under the indenture to the trustee is for informational purposes only, and the trustee's receipt of such shall not constitute actual or constructive notice or knowledge of any information contained therein or determinable from information contained therein, including our compliance with any of our covenants under the indenture (as to which the trustee is entitled to conclusively rely on an officers' certificate).