PROPOSAL 1: TO AUTHORIZE THE FILING OF AN AMENDMENT TO THE COMPANY ’ S RESTATED CERTIFICATE OF INCORPORATION TO EFFECT A REVERSE STOCK SPLIT OF OUR COMMON STOCK, $0.01 PAR VALUE PER SHARE, AT A RATIO IN THE RANGE OF 1:2 TO 1:4, SUCH RATIO WITHIN THAT RANGE TO BE DETERMINED BY THE BOARD OF DIRECTORS CONSISTENT WITH THE GUIDELINES DESCRIBED IN THIS PROXY STATEMENT, AND THE FILING OF SUCH AMENDMENT TO BE IMPLEMENTED, IF AT ALL, NOT LATER THAN NOVEMBER 27, 2016 .

General

Our Board of Directors has adopted and is recommending that our stockholders approve an amendment to our Charter, and thereby authorize the Board of Directors, in their discretion, to effect the Reverse Stock Split no later than November 27, 2016. Holders of our common stock, $0.01 par value per share, are being asked to approve the proposal that Article Fourth of the Charter be amended to effect the Reverse Split (such split to combine a number of outstanding shares of our common stock between two (2) and four (4), such number consisting of only whole shares, into one (1) share of common stock). Pursuant to the law of the State of Delaware, our state of incorporation, the Board of Directors must adopt this amendment to our Charter and submit the amendment to stockholders for their approval. The form of amendment to our Charter to effect the Reverse Stock Split is attached as Appendix B to this proxy statement. The amendment will permit the Board of Directors to effect the Reverse Stock Split at any time on or prior to November 27, 2016. The Board of Directors may effect only one reverse stock split as a result of this authorization. The Board of Directors’ decision as to whether and when to effect the Reverse Stock Split will be based on a number of factors, including market conditions, existing and expected trading prices for our common stock, and the continued listing requirements of The NASDAQ Capital Market. Although our stockholders may approve the Reverse Stock Split, we will not effect the Reverse Stock Split if the Board of Directors does not deem it to be in the best interests of the Company and its stockholders. The Reverse Stock Split, if authorized pursuant to this resolution and if determined by the Board of Directors, in their discretion, to be in the best interests of the Company and its stockholders, will be effected, if at all, on or prior to November 27, 2016.

In determining whether to implement the Reverse Stock Split, the Board of Directors has determined that it will not implement the Reverse Stock Split if, at the time of the Board’s consideration, the Company has already regained compliance with the minimum closing bid price requirement of the NASDAQ Capital Market under NASDAQ Listing Rule 5550(a)(2). In addition, as guidelines to determine the reverse split ratio to be implemented if the proposal is approved, the Board of Directors will target a stock trading price of $2.00 to $3.00 per share immediately following the reverse split. For example, if the common stock is trading at $0.80 per share immediately before the decision to implement the Reverse Stock Split, the Board of Directors would implement the reverse split at a ratio of 1-for-3, which would result in a trading price immediately following the reverse split of $2.40 per share (pre-split trading price of $0.80 times the reverse split ratio of three (3)).

The proposed amendment to our Charter to effect the Reverse Stock Split will not change the number of authorized shares of common stock or preferred stock, or the par value of common stock or preferred stock. As of the date of this proxy statement, we have no definitive, specific plans, arrangements or understandings relating to the issuance of a material amount of additional shares of authorized common stock that will become available following the reverse stock split in the near term.

Purpose and Background of the Reverse Stock Split

On December 1, 2015, we received a deficiency letter from The NASDAQ Stock Market LLC indicating that, for the last 30 consecutive business days ended November 30, 2015, the bid price for our common stock had closed below the minimum $1.00 per share required for continued inclusion on The NASDAQ Capital Market under NASDAQ Listing Rule 5550(a)(2). Pursuant to NASDAQ Listing Rule 5810(c)(3)(A), we were afforded 180 calendar days, or until May 31, 2016, to regain compliance with the

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minimum bid price requirement. On June 1, 2016, we were provided an additional 180-day compliance period by demonstrating that the Company met the applicable market value of publicly held shares requirement for continued listing and all other applicable standards for initial listing on The NASDAQ Capital Market (except the bid price requirement), and by providing written notice of our intention to cure the minimum bid price deficiency during this second grace period, including a cure through the implementation of a reverse stock split. If the Company fails to regain compliance during the second grace period, or by November 27, 2016, the Company’s stock will be subject to delisting by NASDAQ. Our common stock will continue to be listed on The NASDAQ Capital Market during this second grace period.

On August 16, 2016, the Board of Directors approved the proposal authorizing the Reverse Stock Split because the Board of Directors believes that effecting the Reverse Stock Split could be an effective means of regaining compliance with the bid price requirement for continued listing of our common stock on The NASDAQ Capital Market.

NASDAQ Requirements for Continued Listing

Our common stock is quoted on The NASDAQ Capital Market under the symbol “MATN.” One of the requirements for continued listing on the NASDAQ Capital Market is maintenance of a minimum closing bid price of $1.00 per share. On September 15, 2016, the closing market price per share of our common stock was $[●], as reported by The NASDAQ Capital Market. On December 1, 2015, we received a deficiency letter from The NASDAQ Stock Market LLC indicating that the bid price for our common stock had closed below the minimum $1.00 per share required for continued inclusion on The NASDAQ Capital Market as noted above.

We cannot be sure that our stock price will comply with the requirements for continued listing of our common stock on The NASDAQ Capital Market in the future, or that we will comply with the other continued listing requirements. If our common stock loses its status on The NASDAQ Capital Market, our common stock would likely trade in the over-the-counter market.

If our shares were to trade on the over-the-counter market, selling your stock could become more difficult and more expensive because smaller quantities of shares would likely be bought and sold, and transactions could be delayed. In addition, in the event our common stock is delisted, broker-dealers have certain regulatory burdens imposed upon them, which may discourage broker-dealers from effecting transactions in our common shares, further limiting the liquidity of our common shares. Also, some broker-dealers may be required to sell shares of our common stock prior to or shortly after the delisting, creating a potential imbalance of shares in the market. Any one or all of these factors could result in lower prices and larger spreads in the bid and ask prices for common shares.

Such delisting from The NASDAQ Capital Market and continued or further declines in our share price could also greatly impair our ability to raise additional necessary capital through equity or debt financing. In addition, if we were to seek additional capital through an equity financing, such delisting from The NASDAQ Capital Market would be very likely to have a significant and detrimental impact on the terms of an equity financing because:

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In light of the factors mentioned above, our Board of Directors unanimously approved this proposal as a potential means of increasing the bid price of our common stock to above $1.00 per share in compliance with The NASDAQ Stock Market requirements.

There are risks associated with the Reverse Stock Split, including that the Reverse Stock Split may not result in a sustained increase in the per share price of our common stock. We cannot predict whether the Reverse Stock Split will increase the market price for our common stock on a sustained basis. The history of similar stock split combinations for companies in like circumstances is varied. There is no assurance that the market price per share of our common stock after the Reverse Stock Split will rise in proportion to the reduction in the number of shares of our common stock outstanding before the Reverse Stock Split and the market price per share will either exceed or remain in excess of the $1.00 minimum bid price as required by NASDAQ, or that we will otherwise meet the requirements of NASDAQ for continued inclusion for trading on The NASDAQ Capital Market.

The market price of our common stock will also be based on investor perceptions, our performance and other factors, some of which are unrelated to the number of shares outstanding. If the Reverse Stock Split is effected and the market price of our common stock declines, the percentage decline as an absolute number and as a percentage of our overall market capitalization may be greater than would occur in the absence of the Reverse Stock Split. Furthermore, the liquidity of our common stock could be adversely affected by the reduced number of shares that would be outstanding after the Reverse Stock Split.

Principal Effects of the Reverse Stock Split

If the stockholders approve the proposal to authorize the Board of Directors to implement the Reverse Stock Split and the Board of Directors implements the Reverse Stock Split, we will amend the existing provision of our Charter relating to our authorized capital to add the following paragraph at the end thereof:

“Upon the effectiveness of the certificate of amendment to the restated certificate of incorporation containing this sentence, each [*] shares of the Common Stock issued and outstanding as of the date and time immediately preceding [date on which the certificate of amendment is filed], the effective date of a reverse stock split (the “Split Effective Date”), shall be automatically changed and reclassified, as of the Split Effective Date and without further action, into one (1) fully paid and non-assessable share of Common Stock. There shall be no fractional shares issued. A holder of record of Common Stock on the Split Effective Date who would otherwise be entitled to a fraction of a share shall, in lieu thereof, be entitled to receive a cash payment in an amount equal to the fraction to which the stockholder would otherwise be entitled multiplied by the closing price of the Common Stock, as reported by NASDAQ, on the last trading day prior to the Split Effective Date (or if such price is not available, such price determined by the Corporation’s board of directors).”

By approving this amendment, stockholders will approve the combination of any whole number of shares of common stock between and including two (2) and four (4) into one (1) share. The certificate of amendment filed with the Secretary of State of the State of Delaware will include only that number determined by the Board of Directors to be in the best interests of the Corporation and its stockholders. In accordance with these resolutions, the Board of Directors will not implement any amendment providing for a different split ratio.

The Reverse Stock Split will be effected simultaneously for all issued and outstanding shares of common stock and the exchange ratio will be the same for all issued and outstanding shares of common stock. As soon as practicable after the effective date of the split, stockholders will be notified that the reverse stock split has been effected. The Reverse Stock Split will affect all of our stockholders uniformly and will not affect any stockholder’s percentage ownership interests in the Company, except to the extent that the Reverse Stock Split results in any of our stockholders owning a fractional share. After the Reverse Stock Split, the shares of our common stock will have the same voting rights and rights to dividends and distributions and will be identical in all other respects to our common stock now authorized. Our common stock outstanding following the reverse stock split will remain fully paid and non-assessable. The Reverse Stock Split will not affect the Company

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continuing to be subject to the periodic reporting requirements of the Exchange Act. The Reverse Stock Split is not intended to be, and will not have the effect of, a “going private transaction” covered by Rule 13e-3 under the Exchange Act.

The Reverse Stock Split may result in some stockholders owning “odd-lots” of less than 100 shares of our common stock. Brokerage commissions and other costs of transactions in odd-lots are sometimes higher than the costs of transactions in “round-lots” of even multiples of 100 shares.

Book-Entry Shares

If you hold shares of common stock in a book-entry form, you will receive a transmittal letter from the Company’s transfer agent as soon as practicable after the effective time of the Reverse Stock Split with instructions on how to exchange your shares. After you submit your completed transmittal letter, if you are entitled to post-split shares of our common stock, a transaction statement will be sent to your address of record as soon as practicable after the effective date of the split indicating the number of shares of common stock you hold. If you are entitled to a payment in lieu of any fractional interest, a check will be mailed to you at your registered address as soon as practicable after the effective date of the split. See “Fractional Shares” below for additional information.

Certificated Shares

The Company expects that our transfer agent will act as exchange agent for purposes of implementing the exchange of stock certificates. Holders of pre-split shares will be asked to surrender to the exchange agent certificates representing pre-split shares in exchange for certificates representing post-split shares in accordance with the procedures to be set forth in a letter of transmittal to be sent by the Company or its exchange agent. No new certificates will be issued to a stockholder until such stockholder has surrendered such stockholder’s outstanding certificate(s) together with the properly completed and executed letter of transmittal to the exchange agent. Any pre-split shares submitted for transfer, whether pursuant to a sale or other disposition, or otherwise, will automatically be exchanged for post-split shares.

Some stockholders hold their shares of common stock in certificate form or a combination of certificate and book-entry form. We expect that our transfer agent will act as exchange agent for purposes of implementing the exchange of stock certificates, if applicable. If you are a stockholder holding pre-split shares in certificate form, you will receive a transmittal letter from the Company’s transfer agent as soon as practicable after the effective time of the Reverse Stock Split. The transmittal letter will be accompanied by instructions specifying how you can exchange your certificate representing the pre-split shares of our common stock for a statement of holding, together with any payment of cash in lieu of fractional shares to which you are entitled. When you submit your certificate representing the pre-split shares of our common stock, your post-split shares of our common stock will be held electronically in book-entry form. This means that, instead of receiving a new stock certificate, you will receive a statement of holding that indicates the number of post-split shares you own in book-entry form. We will no longer issue physical stock certificates unless you make a specific request for a share certificate representing your post-split ownership interest.

STOCKHOLDERS SHOULD NOT DESTROY ANY STOCK CERTIFICATE(S) AND SHOULD NOT SUBMIT ANY CERTIFICATE(S) UNTIL REQUESTED TO DO SO.

Beginning on the effective time of the Reverse Stock Split, each certificate representing pre-split shares will be deemed for all corporate purposes to evidence ownership of post-split shares.

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Fractional Shares

No fractional shares will be issued in connection with the Reverse Stock Split. Stockholders of record who otherwise would be entitled to receive fractional shares because they hold a number of pre-split shares not evenly divisible by the number of pre-split shares for which each post-split share is to be exchanged, will be entitled, upon surrender to the exchange agent of certificates representing such shares, to a cash payment in lieu thereof at a price equal to the fraction to which the stockholder would otherwise be entitled multiplied by the closing price of the common stock, as reported by NASDAQ, on the last trading day prior to the effective date of the split (or if such price is not available, the price determined by the Board of Directors). The ownership of a fractional interest will not give the holder thereof any voting, dividend, or other rights except to receive payment therefor as described herein.

Stockholders should be aware that, under the escheat laws of the various jurisdictions where stockholders reside, where the Company is domiciled, and where the funds will be deposited, sums due for fractional interests that are not timely claimed after the effective date of the Reverse Stock Split may be required to be paid to the designated agent for each such jurisdiction, unless correspondence has been received by the Company or the exchange agent concerning ownership of such funds within the time permitted in such jurisdiction. Thereafter, stockholders otherwise entitled to receive such funds will have to seek to obtain them directly from the state to which they were paid. Each holder should seek advice based on the holder’s particular circumstances from an independent tax advisor.

Effect on Stock Plans

As of September 15, 2016, options to purchase 4,049,415 shares of common stock are outstanding under the Company’s two equity incentive plans, the 2015 Equity Incentive Plan (the “2015 Plan”) and the 2005 Stock Plan, and 676,366 options remain available for issuance under the 2015 Plan. If the Reverse Stock Split is approved by our stockholders and our Board of Directors decides to implement the Reverse Stock Split, as of the effective date, the number of all outstanding equity awards, the number of shares available for issuance and the exercise price, grant price or purchase price, as applicable, relating to any award under our stock plans, will be proportionately adjusted using the reverse stock split ratio selected by our Board of Directors (subject to the treatment of fractional shares to be determined by our Board of Directors). Our Board of Directors has also authorized the Company to effect any other changes necessary, desirable or appropriate to give effect to the Reverse Stock Split, including any applicable technical, conforming changes. For example, if a 1-for-2 reverse stock split is effected, the 676,366 shares that remain available for issuance under the 2015 Plan as of September 15, 2016, would be adjusted to equal approximately 338,183 shares. In addition, the exercise price per share of each outstanding stock option would be increased by a factor of 2 and the number of shares subject to each outstanding stock option would be reduced by 1/2. Following these changes, the aggregate exercise price payable by the optionee to the Company would remain the same and the percentage of the Company that the optionee purchased would remain the same, but the price per share would increase and the number of shares acquired would decrease.

Accounting Matters

The Reverse Stock Split will not affect the stockholders’ equity accounts on our balance sheet. However, because the par value of our common stock will remain unchanged on the effective date of the split, the components that make up the common stock capital account and the additional paid-in capital account will change by offsetting amounts. Depending on the size of the reverse stock split the Board of Directors implements, the stated capital component will be reduced to an amount between one-half (1/2) and one-fourth (1/4) of its present amount, and the additional paid-in capital component will be increased by the amount which the stated capital is reduced. The per share net loss and net book value of our common stock will be increased because there will be fewer shares of common stock outstanding. All per share amounts for all periods for which we present financial statements will be restated to reflect the Reverse Stock Split.

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No Dissenters’ Rights

Under the Delaware General Corporation Law, the Company’s stockholders will not be entitled to dissenters’ rights with respect to the Reverse Stock Split, and we do not intend to independently provide stockholders with any such right.

Material United States Federal Income Tax Consequences of the Reverse Stock Split

Each holder of common stock is hereby notified that any discussion of U.S. Federal tax issues in this proxy statement has been included by the Company in furtherance of the Reverse Stock Split on the terms described herein, and each such holder should seek advice based on his, her, or its particular circumstances from an independent tax advisor.

The following discussion describes the anticipated material United States Federal income tax consequences to “U.S. holders” (as defined below) of Company capital stock relating to the Reverse Stock Split. This discussion is based upon the Internal Revenue Code of 1986, as amended (the “Code”), Treasury Regulations, judicial authorities, published positions of the Internal Revenue Service (“IRS”), and other applicable authorities, all as currently in effect and all of which are subject to change or differing interpretations (possibly with retroactive effect). We have not obtained a ruling from the IRS or an opinion of legal or tax counsel with respect to the tax consequences of the Reverse Stock Split. The following discussion is for information purposes only and is not intended as tax or legal advice. Each holder should seek advice based on the holder’s particular circumstances from an independent tax advisor.

For purposes of this discussion, the term “U.S. holder” means a beneficial owner of Company capital stock that is for United States Federal income tax purposes:

This discussion assumes that a U.S. holder holds Company capital stock as a capital asset within the meaning of Code Section 1221. This discussion does not address all of the tax consequences that may be relevant to a particular Company stockholder or to Company stockholders that are subject to special treatment under United States Federal income tax laws including, but not limited to, financial institutions, tax-exempt organizations, insurance companies, regulated investment companies, persons that are broker-dealers, traders in securities who elect the mark-to-market method of accounting for their securities, or Company stockholders holding their shares of Company capital stock as part of a “straddle,” “hedge,” “conversion transaction,” or other integrated transaction. This discussion also does not address the tax consequences to the Company, or to Company stockholders that own 5% or more of the Company’s capital stock, are affiliates of Company, or are not U.S. holders. In addition, this discussion does not address other United States Federal taxes (such as gift or estate taxes or alternative minimum taxes), the tax consequences of the Reverse Stock Split under state, local, or foreign tax laws or certain tax reporting requirements that may be applicable with respect to the reverse stock split. No assurance can be given that the IRS would not assert, or that a court would not sustain, a position contrary to any of the tax consequences set forth below.

If a partnership (or other entity treated as a partnership for United States Federal income tax purposes) is a Company stockholder, the tax treatment of a partner in the partnership (or any equity owner of such other entity) will generally depend upon the status of the person and the activities of the partnership or other entity treated as a partnership for United States Federal income tax purposes.

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Tax Consequences of the Reverse Stock Split Generally

We believe that the Reverse Stock Split will qualify as a “reorganization” under Section 368(a)(1)(E) of the Code. Accordingly, provided that the fair market value of the post-Reverse Stock Split shares is equal to the fair market value of the pre-Reverse Stock Split shares surrendered in the Reverse Stock Split:

Cash Received Instead of a Fractional Share

A U.S. holder who receives cash instead of a fractional share of post-Reverse Stock Split shares will be treated as having received the fractional share of post-Reverse Stock Split shares pursuant to the Reverse Stock Split and then as having exchanged the fractional share of post-Reverse Stock Split shares for cash in a redemption by the Company. In general, this deemed redemption will be treated as a sale or exchange, provided the redemption is not essentially equivalent to a dividend as discussed below. Gain or loss generally will be recognized based on the difference between the amount of cash received and the portion of the U.S. holder’s adjusted tax basis of the pre-Reverse Stock Split shares exchanged in the Reverse Stock Split which is allocable to such fractional share. Such gain or loss generally will be long-term capital gain or loss if the U.S. holder’s holding period for such pre-Reverse Stock Split shares is more than one year as of the effective date of the Reverse Stock Split, and otherwise will be short-term capital gain or loss.

The receipt of cash is “not essentially equivalent to a dividend” if the reduction in a U.S. holder’s proportionate interest in Company resulting from the Reverse Stock Split (taking into account for this purpose shares of common stock which such holder is considered to own under certain attribution rules) is considered a “meaningful reduction” given such U.S. holder’s particular facts and circumstances. The IRS has ruled that a small reduction by a minority stockholder whose relative stock interest is minimal and who exercises no control over the affairs of a corporation can satisfy this test. If the receipt of cash in lieu of a fractional share is not treated as capital gain or loss under the test just described, it will be treated first as ordinary dividend income to the extent of a U.S. holder’s ratable share of Company’s current and accumulated earnings and profits, then as a tax-free return of capital to the extent of the portion of the U.S. holder’s adjusted tax basis of the pre-Reverse Stock Split shares which is allocable to such fractional share, and any remaining amount will be treated as capital gain.

Information Reporting and Backup Withholding

Cash payments received by a U.S. holder of Company capital stock pursuant to the Reverse Stock Split are subject to information reporting, and may be subject to backup withholding at the applicable rate specified by the U.S. Internal Revenue Service (currently 28%) if the holder fails to provide a valid taxpayer identification number and comply with certain certification procedures or otherwise establish an exemption from backup withholding. Backup withholding is not an additional United States Federal income tax. Rather, the U.S. Federal income tax liability of the person subject to backup withholding will be reduced by the amount of the tax withheld. If backup withholding results in an overpayment of taxes, a refund may be obtained provided that the required information is timely furnished to the IRS.

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Reservation of Right to Abandon Reverse Stock Split

We reserve the right to not file the certificate of amendment and to abandon any reverse stock split without further action by our stockholders at any time before the effectiveness of the filing with the Secretary of the State of Delaware of the certificate of amendment, even if the authority to effect this amendment is approved by our stockholders at the Special Meeting. By voting in favor of a reverse stock split, you are expressly also authorizing the Board to delay, not proceed with, and abandon, this proposed amendment if it should so decide, in its discretion, that such action is in the best interests of our stockholders.

Vote Required and Board of Directors’ Recommendation

Approval of the amendment to our Charter to effect the Reverse Stock Split requires an affirmative vote of a majority of the common stock outstanding and entitled to vote at the Special Meeting. Abstentions and broker non-votes will be counted towards the vote total for this proposal and will have the same effect as “against” votes.

THE BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR” THE PROPOSAL TO AUTHORIZE THE FILING OF AN AMENDMENT TO THE COMPANY’S RESTATED CERTIFICATE OF INCORPORATION TO EFFECT A REVERSE STOCK SPLIT OF OUR COMMON STOCK, $0.01 PAR VALUE PER SHARE, AT A RATIO IN THE RANGE OF 1:2 TO 1:4, SUCH RATIO WITHIN THAT RANGE TO BE DETERMINED BY THE BOARD OF DIRECTORS CONSISTENT WITH THE GUIDELINES DESCRIBED IN THIS PROXY STATEMENT, AND THE FILING OF SUCH AMENDMENT TO BE IMPLEMENTED, IF AT ALL, NOT LATER THAN NOVEMBER 27, 2016.

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