Provisions of the Plan. This PSU award is subject to the provisions of the Plan. The Participant acknowledges receipt of the Plan, along with the Prospectus relating to the Plan.

Provisions of Plan Control. This grant is subject to all the terms, conditions and provisions of the Plan, including, without limitation, [Section 17.13] of the Plan (Section 409A of the Code) and the amendment provisions of the Plan, and to such rules, regulations and interpretations relating to the Plan as may be adopted by the Board of Directors of the Company and as may be in effect from time to time. Any capitalized term used but not defined herein shall have the meaning ascribed to such term in the Plan. The Plan is incorporated herein by reference. If and to the extent that this grant conflicts or is inconsistent with the terms, conditions and provisions of the Plan, the Plan shall control, and this grant shall be deemed to be modified accordingly.

This option is subject to the provisions of the Plan (including the provisions relating to amendments to the Plan), a copy of which is furnished to the Participant with this option.

Incorporation of Plan Provisions. These Terms and Conditions and the Agreement are made pursuant to the Plan, the provisions of which are hereby incorporated by reference. Capitalized terms not otherwise defined herein shall have the meanings set forth for such terms in the Plan. In the event of a conflict between the terms of these Terms and Conditions and the Agreement and the Plan, the terms of the Plan shall govern.

Provisions of the Plan. Capitalized terms used herein and not defined herein shall have the meanings set forth in the Plan. This Agreement and the Award set forth herein shall be subject to and shall be governed by the terms set forth in the Plan, a copy of which has been furnished to Executive and which is incorporated by reference into this Agreement. In the event of any conflict between this Agreement and the Plan, the Plan shall control.

Agreement Subject to the Plan. This Agreement is subject to the provisions of the Plan and shall be interpreted in accordance therewith. In the event that the

Stock Subject to the Plan. Subject to adjustment upon changes in capitalization of the Company as provided in Section 14, the maximum aggregate number of Shares that may be subject to Awards and sold under the Plan will be equal to # 1,000,000 Shares, plus # any Shares subject to awards granted under the Tocagen, Inc. 2009 Equity Incentive Plan, the Tocagen, Inc. 2017 Equity Incentive Plan, and the Forte Biosciences Inc. 2018 Equity Incentive Plan that, after the date of stockholder approval of the Plan, expire or otherwise terminate without having been exercised or issued in full, are tendered to or withheld by the Company for payment of an exercise price or for tax withholding obligations, or are forfeited to or repurchased by the Company due to failure to vest, with the maximum number of Shares to be added to the Plan pursuant to clause (b) equal to 1,102,341. In addition, Shares may become available for issuance under Section 3.2. The Shares may be authorized but unissued, or reacquired Common Stock.

Subject to adjustment as provided in Section 13 of the Plan, a total of 250,000 shares of Company Stock may be issued pursuant to Awards under the Plan. Subject to adjustment as provided in Section 13, no more than an aggregate of 250,000 shares of Company Stock may be issued pursuant to the exercise of Incentive Stock Options granted under the Plan (including shares issued pursuant to the exercise of Incentive Stock Options that are the subject to disqualifying dispositions within in the meaning of Sections 421 and 422 of the Code).

Restricted Stock Subject to Plan. This Award is subject to the Plan as approved by the Company’s stockholders and as may thereafter be amended or modified in accordance with its terms. The terms and provisions of the Plan as it may be amended from time to time are hereby incorporated herein by reference. In the event of a conflict between any term or provision contained herein and a term or provision of the Plan, the applicable terms and provisions of the Plan will govern and prevail.

Subject to adjustment as provided below, the total number of shares of Stock reserved and available for issuance in connection with the Plan is Ten Million Four Hundred Ninety Thousand Seven Hundred Eighty-Four (10,490,784). Any Stock issued hereunder may consist, in whole or in part, of authorized and unissued shares or treasury shares. If there is a merger, reorganization, consolidation, recapitalization, share dividend, share split, reverse split, combination of shares or other change in corporate structure of the Company affecting the Stock, such substitution or adjustment shall be made in the aggregate number of shares of Stock reserved for issuance under the Plan, and in the number of shares deemed to be held in any Account, as may be approved by the Committee in its sole discretion.