Exercise of Option. Effective as of today, , , the undersigned (“Participant”) hereby elects to exercise Participant’s option (the “Option”) to purchase shares of the Common Stock (the “Shares”) of [[Organization A:Organization]] (the “Company”) under and pursuant to the 2015 Equity Incentive Plan (the “Plan”) and the Stock Option Agreement dated , (the “Option Agreement”).

Exercise of Option. Once vested, the Participant may exercise this Option, in whole or in part, at any time during the term as specified above but not after ten (10) years from the Date of Grant; provided, that if the Participant dies, this Option, if vested, may be exercised within three (3) years after death, but not after ten (10) years from the Date of Grant, by the Participant’s estate or by the person or persons who acquire the right to exercise this Option by bequest, inheritance or otherwise by reason of such death. ​ and the Participant recognize that this Agreement in no way restricts the right of ​ to terminate the Participant’s membership consistent with applicable Delaware laws.

Exercise of Option. Exercise of the purchase rights represented by this Option may be made, in whole or in part, at any time or times during the Exercise Period by delivery to the Company at its executive offices of a duly executed copy of the Notice of Exercise Form annexed hereto; and, if the Holder opts to make cash payment, within 3 business days of the date said Notice of Exercise is delivered to the Company, the Company shall have received payment of the aggregate Exercise Price of the shares thereby purchased by wire transfer or cashier’s check or otherwise by agreement with the Company. Notwithstanding anything herein to the contrary, the Holder shall not be required to physically surrender this Option to the Company until the Holder has purchased all of the Option Shares available hereunder and the Option has been exercised in full, in which case, the Holder shall surrender this Option to the Company for cancellation within 3 business days of the date the final Notice of Exercise is delivered to the Company.

Exercise of Option. An Option to Extend shall be exercised by ​, if at all, only in the manner set forth in this Section 2.2. ​ shall deliver notice (the “Exercise Notice”) to ​ not more than fifteen (15) months nor less than nine (9) months prior to the expiration of the Lease Term or the applicable Option Term, as applicable, stating that ​ is exercising its Option to Extend, which election shall be irrevocable regardless of the fact that the

Exercise of Option. This Option shall be exercisable during its term in accordance with the Vesting Schedule set out in the Notice of Grant and with the provisions of Sections 10 and 11 of the Plan as follows:

Exercise of Option. Effective as of today, the undersigned (“Optionee”) hereby elects to exercise Optionee’s option to purchase ​ shares of the Common Stock (the “Shares”) of Assembly Biosciences, Inc. (the “Company”) under and pursuant to the Company’s 2019 Inducement Award Plan (as amended from time to time, the “Plan”) and the Notice of Stock Option Grant dated ​, 20​ with its attached Stock Option Agreement (the “Option Agreement”). The purchase price for the Shares shall be ​ as required by this Option Agreement. Optionee herewith delivers to the Company the full Exercise Price for the Shares.

Option Exercise Price. The exercise price per Share subject to each Option shall be set by the Administrator, but shall not be less than one hundred percent (100%) of the Fair Market Value of a Share on the date the Option is granted (or, as to Incentive Stock Options, on the date the Option is modified, extended or renewed for purposes of Section 424(h) of the Code). In addition, in the case of Incentive Stock Options granted to a Greater Than 10% Stockholder, such price shall not be less than one hundred ten percent (110%) of the Fair Market Value of a Share on the date the Option is granted (or the date the Option is modified, extended or renewed for purposes of Section 424(h) of the Code).

The Option shall not be exercisable as of the Grant Date set forth in the Grant Notice. After the Grant Date, to the extent not previously exercised, and subject to termination or acceleration as provided in these Standard Terms and Conditions and the Plan, the Option shall be exercisable only to the extent it becomes vested, as described in the Grant Notice, these Standard Terms and Conditions and/or the terms of the Plan, to purchase up to that number of shares of Common Stock as set forth in the Grant Notice, provided that (except as may be provided otherwise in Section 4 below) the Participant remains employed with the Company and does not experience a termination of employment.

Exercise of Option. This Option may be exercised in whole or in part at any time or times prior to its expiration; provided that the first exercise of this Option shall not occur before the fourth anniversary of the date on which the Option was granted. Notwithstanding the foregoing, if the Participant’s employment with the Corporation or a Subsidiary Company is terminated by reason of the Participant’s Retirement or death before the fourth anniversary of the date on which the Option was granted, the Participant (or, in the case of death, the Participant’s Beneficiary) may first exercise this Option on the later of the first anniversary of the date on which this Option was granted or the effective date of the Participant’s Retirement or death. Notice of the exercise of all or any part of this Option shall be given in the manner prescribed by the Secretary of the Corporation. Such notice shall be irrevocable, shall specify the number of shares to be purchased and the purchase price to be paid therefore, and must be accompanied by the payment of the purchase price as provided in paragraph 3(c) herein. Upon the exercise of such Option, the Common Stock purchased will be distributed.

Exercise of Option. Landlord will give notice to Tenant (an “Offering Notice”) setting forth Landlord’s intent to construct the Station 5 Building and to make the Station 5 Building available for lease. The Offering Notice shall include # the rentable square footage of the Station 5 Building that Landlord intends to construct, for which rentable square footage Landlord shall have obtained approvals through the Site Plan and Architectural Review process of the City of San Mateo, # the six-month time period during which Landlord anticipates completing the base building improvements of the Station 5 Building and delivering possession thereof for completion of tenant improvements, and # a copy of the building plans for the Station 5 Building. Tenant shall exercise the Expansion Option, if at all, by giving Landlord unconditional, irrevocable written notice of such election (the “Expansion Exercise Notice”) no later than thirty (30) days after the date of the Offering Notice, the time of such exercise being of the essence. Tenant’s Expansion Exercise Notice shall set forth the rentable square footage of the Station 5