Subsequent events	12 Months Ended
Dec. 31, 2023
Subsequent events.
Subsequent events	16. Subsequent events In January 2024, the joint research committee under the Genentech Collaboration Agreement reached a decision to discontinue research activities associated with Genentech Collaboration Program #3 and, as a result, the Company expects to recognize revenue of approximately $10.4 million in the first quarter of 2024 associated with the completion of its performance obligations, including $7.4 million related to the expiration of remaining material rights. Genentech Collaboration Programs #1 and #4 remain ongoing.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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