Commitments and contingencies	3 Months Ended
Mar. 31, 2023
Commitments and contingencies
Commitments and contingencies	7. Commitments and contingencies Employment agreements The Company entered into employment agreements, or the Employment Agreements, with certain key personnel providing for compensation and severance in certain circumstances, as defined in the respective Employment Agreements. The Employment Agreements may be terminated by either the Company or the employees in accordance with the respective Employment Agreements (subject to the payment of severance upon certain terminations) and provide for annual pay adjustments and bonuses at the discretion of the Board of Directors. Employee benefit plan The Company maintains a defined-contribution plan under Section 401(k) of the Internal Revenue Code, or the 401(k) Plan. The 401(k) Plan covers all employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. The Company assumes all administrative costs of the 401(k) Plan and makes matching contributions as defined in the 401(k) Plan document. The Company made matching contributions of $0.1 million to the 401(k) Plan for each of the three months ended March 31, 2023 and 2022, respectively. Legal proceedings The Company is not a party to any material litigation and does not have contingency reserves established for any litigation liabilities. At each reporting date, the Company evaluates whether a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. License agreements The Company entered into various license agreements to further discover, develop and commercialize certain technologies and treatments. The Company may need to pay developmental and regulatory milestone payments of up to approximately $2.6 million. In addition, the Company may need to pay royalty rates on net product sales, a portion of certain sublicense and collaboration payments, and certain commercial milestone payments of up to approximately $1.5 million, if any. The Company did not make any development, regulatory, or commercial milestone payments during the three months ended March 31, 2023 and 2022, respectively. Whitehead Letter Agreement On November 17, 2022, the Company entered into a Letter Agreement, or the Letter Agreement, with the Whitehead Institute of Biomedical Research, or Whitehead, which became effective on January 4, 2023 upon the satisfaction of the conditions described therein. The Letter Agreement supplements the Exclusive Patent License Agreement entered into between the Company and Whitehead on June 25, 2009 (as amended on December 17, 2009, March 21, 2013, August 21, 2017 and July 21, 2020, the License Agreement). Pursuant to the Letter Agreement, Whitehead and the Company agreed that certain payments received by the Company from the Collaborator (as defined in the Letter Agreement) (i.e., a corporate partner, as defined in the License Agreement) would be excluded from the Company’s payment obligations to Whitehead. The Company and Whitehead further agreed, among other things, that the Company will make certain payments to Whitehead (i) as Net Sales (as defined in the License Agreement) as long as the Company receives those payments from the Collaborator on a specified number of products purchased by the Collaborator and (ii) upon the achievement of certain milestones whether by the Company or the Collaborator.

Commitments and contingencies

3 Months Ended

Mar. 31, 2023

7. Commitments and contingencies

Employment agreements

The Company entered into employment agreements, or the Employment Agreements, with certain key personnel providing for compensation and severance in certain circumstances, as defined in the respective Employment Agreements. The Employment Agreements may be terminated by either the Company or the employees in accordance with the respective Employment Agreements (subject to the payment of severance upon certain terminations) and provide for annual pay adjustments and bonuses at the discretion of the Board of Directors.

Employee benefit plan

The Company maintains a defined-contribution plan under Section 401(k) of the Internal Revenue Code, or the 401(k) Plan. The 401(k) Plan covers all employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. The Company assumes all administrative costs of the 401(k) Plan and makes matching contributions as defined in the 401(k) Plan document. The Company made matching contributions of $0.1 million to the 401(k) Plan for each of the three months ended March 31, 2023 and 2022, respectively.

Legal proceedings

The Company is not a party to any material litigation and does not have contingency reserves established for any litigation liabilities. At each reporting date, the Company evaluates whether a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies.

License agreements

The Company entered into various license agreements to further discover, develop and commercialize certain technologies and treatments. The Company may need to pay developmental and regulatory milestone payments of up to approximately $2.6 million. In addition, the Company may need to pay royalty rates on net product sales, a portion of certain sublicense and collaboration payments, and certain commercial milestone payments of up to approximately $1.5 million, if any. The Company did not make any development, regulatory, or commercial milestone payments during the three months ended March 31, 2023 and 2022, respectively.

Whitehead Letter Agreement

On November 17, 2022, the Company entered into a Letter Agreement, or the Letter Agreement, with the Whitehead Institute of Biomedical Research, or Whitehead, which became effective on January 4, 2023 upon the satisfaction of the conditions described therein. The Letter Agreement supplements the Exclusive Patent License Agreement entered into between the Company and Whitehead on June 25, 2009 (as amended on December 17, 2009, March 21, 2013, August 21, 2017 and July 21, 2020, the License Agreement). Pursuant to the Letter Agreement, Whitehead and the Company agreed that certain payments received by the Company from the Collaborator (as defined in the Letter Agreement) (i.e., a corporate partner, as defined in the License Agreement) would be excluded from the Company’s payment obligations to Whitehead. The Company and Whitehead further agreed, among other things, that the Company will make certain payments to Whitehead (i) as Net Sales (as defined in the License Agreement) as long as the Company receives those payments from the Collaborator on a specified number of products purchased by the Collaborator and (ii) upon the achievement of certain milestones whether by the Company or the Collaborator.