Item 1.01. Entry into a Material Definitive Agreement.
On September 21, 2017, Juno Therapeutics, Inc. (the “Company”), entered into an underwriting agreement (the “Underwriting
Agreement”) with Morgan Stanley & Co. LLC and J.P. Morgan Securities LLC, as representatives of the several underwriters named in Schedule I thereto (the “Underwriters”), relating to an underwritten public offering of
6,100,000 shares of common stock of the Company (the “Underwritten Shares”) at a price of $41.00 per share. The net proceeds to the Company from this offering and the concurrent private placement described below are expected to be
approximately $262.2 million, after deducting underwriting discounts and commissions and other estimated offering expenses. The Company intends to use the net proceeds of the offering and the concurrent private placement described below for
general corporate purposes and working capital. The Company has granted the Underwriters a 30-day option to purchase up to an additional 915,000 shares of common stock (together with the Underwritten Shares, the “Shares”). The closing of
the offering is expected to occur on or about September 26, 2017, subject to the satisfaction of customary closing conditions.
The
offering is being made pursuant to the Company’s effective registration statement on Form S-3 (Registration Statement No. 333-220537) (the “Registration Statement”) previously filed with the Securities and Exchange Commission,
the related registration statement filed on September 22, 2017 pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “Securities Act”), the preliminary prospectus relating to the offering included therein and a final
prospectus dated September 21, 2017.
The Underwriting Agreement contains customary representations, warranties and agreements by the
Company, customary conditions to closing, indemnification obligations of the Company and the Underwriters, including for liabilities under the Securities Act, other obligations of the parties and termination provisions. The representations,
warranties and covenants contained in the Underwriting Agreement were made only for purposes of such agreement and as of specific dates, were solely for the benefit of the parties to such agreement, and may be subject to limitations agreed upon by
the contracting parties. In addition, pursuant to the terms of the Underwriting Agreement, certain officers and directors of the Company have entered into “lock-up” agreements with the Underwriters in substantially the form included as
Exhibit A to the Underwriting Agreement, which generally prohibit the sale, transfer or other disposition of securities of the Company for a 90-day period, subject to certain exceptions.
In addition, the Company entered into a Share Purchase Agreement and Omnibus Amendment (the “Share Purchase Agreement”) with Celgene
Corporation and certain of its subsidiaries (collectively, “Celgene”), pursuant to which the Company has agreed to sell and Celgene has agreed to buy 659,415 shares of our common stock in a private placement exempt from the
registration requirements of the Securities Act, at a sale price equal to the price to the public in the offering made pursuant to the Underwriting Agreement and Registration Statement (the “Public Offering”). The closing of this purchase
will be conditioned on, and concurrent with, the initial closing of the Public Offering. Celgene has also agreed to purchase in subsequent closings and at the same price a number of shares equal to approximately 10.81% of the number of shares sold
in any full or partial exercise of the Underwriters’ option to purchase additional shares in the Public Offering, up to a maximum of 98,912 additional shares of common stock. The Company will receive the full proceeds and will not pay any
underwriting discounts or commission with respect to the shares that are sold in the private placement. The number of shares we will sell to Celgene will constitute approximately 9.76% of the aggregate number of the shares sold in the Public
Offering and the concurrent private placement to Celgene, which is equal to the percentage of our common stock Celgene beneficially owned following its last exercise of its top-up purchase rights pursuant to the share purchase agreement previously
entered into with Celgene in June 2015 (the “First Celgene SPA”), as disclosed by the Company in a filing made on Form 8-K on June 29, 2015 (the “June 2015 8-K”). The Share Purchase Agreement also amends the terms of the
previously disclosed Voting and Standstill Agreement and Registration Rights Agreement, each entered into between the Company and Celgene on June 29, 2015, and each also previously disclosed in the June 2015 8-K, in order to subject the shares
purchased in the Share Purchase Agreement to the same terms and conditions under such agreements as if the shares had been purchased pursuant to the First Celgene SPA.
Based on the number of shares of Juno’s common stock outstanding as of September 21, 2017, upon the closing of the Public Offering and
the concurrent private placement to Celgene, Juno will have 113,288,567 shares of common stock outstanding (or 114,302,479 shares of common stock outstanding if the Underwriters fully exercise their option to purchase additional shares in the Public
Offering).
The foregoing description of the Underwriting Agreement and the Share Purchase Agreement is not complete and is qualified in
its entirety by reference to the full text of the Underwriting Agreement and the Share Purchase Agreement, copies of which are filed herewith as Exhibits 1.1 and 10.1, respectively, to this Current Report on Form 8-K and are incorporated herein by
reference.