Commitments and Contingencies	12 Months Ended
Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	9. Commitments and Contingencies Intellectual Property Agreements Charpentier License Agreements In April 2014, the Company entered into certain technology license agreements with Dr. Emmanuelle Charpentier pursuant to which the Company licensed certain intellectual property rights under joint ownership from Dr. Charpentier to develop and commercialize products for the treatment or prevention of human diseases. In connection therewith, Dr. Charpentier is entitled to receive nominal clinical milestone payments, low single digit percentage of sublicensing payments received under any sublicense agreement with a third party, and low single-digit percentage royalties based on annual net sales of licensed products and services by the Company and its affiliates and sublicensees. The Company paid an immaterial amount of fees to Dr. Charpentier under the Charpentier License Agreements. Research, Manufacturing and License Agreements The Company has engaged several research institutions and companies to identify new delivery strategies and applications of the Company’s gene editing technology. The Company is also a party to a number of license agreements which require significant upfront payments and may be required to make future royalty payments and potential milestone payments from time to time. In addition, the Company is also a party to intellectual property agreements, which require maintenance and milestone payments from time to time. Further, the Company is a party to a number of manufacturing agreements that require upfront payments for the future performance of services. In association with these agreements, on a product-by-product basis, the counterparties are eligible to receive up to low eight-digit potential payments upon specified research, development and regulatory milestones. In addition, on a product-by-product basis, the counterparties are eligible to receive potential commercial milestone payments based on specified annual sales thresholds. The potential payments are low-single digit percentages of the specified annual sales thresholds. The counterparties are also eligible to receive low single-digit royalties on future net sales. Under certain circumstances and if certain contingent future events occur, Vertex is eligible to receive up to $395.0 million in potential specified research, development, regulatory and commercial milestones and tiered single-digit percentage royalties on future net sales related to a specified target under an amendment to the 2015 Collaboration Agreement. Vertex also has the option to conduct research at their own cost in certain defined areas that, if beneficial to the CASGEVY program and ultimately achieves regulatory approval, then the Company could owe Vertex certain milestone payments aggregating to high eight digits, subject to certain limitations on the profitability of the CASGEVY program. Under the A&R Vertex JDCA, the Company has an option to defer specified costs on the CASGEVY program in excess of $110.3 million for the years ended December 31, 2022, 2023 and 2024. The $110.3 million for 2023 does not include amounts attributable to our share of certain costs arising from a license agreement between Vertex and a third party, which we agreed to pay to Vertex upon the occurrence of an event specified in Amendment No. 1 to the A&R Vertex JDCA. In 2023 and 2022, the Company exercised its option to defer specified costs on the CASGEVY program in excess of the deferral limit under A&R Vertex JDCA. The Company deferred $80.9 million and $36.1 million of its share of costs incurred under the arrangement for the years ended December 31, 2023 and 2022, respectively, as spending on the CASGEVY program exceeded a specified amount. Any deferred amounts are only payable to Vertex as an offset against future profitability of the CASGEVY program and the amounts payable are capped at a specified maximum amount per year. These deferred costs on the CASGEVY program will be recognized by us when recoverability of such deferred amounts by Vertex is probable and the amount can be reasonably estimated. As of December 31, 2023 and 2022, no such deferred amounts have been recognized . Refer to Note 8 for further discussion on the Company’s arrangements with Vertex. Litigation In the ordinary course of business, the Company is from time to time involved in lawsuits, investigations, proceedings and threats of litigation related to, among other things, the Company’s intellectual property estate (including certain in-licensed intellectual property), commercial arrangements and other matters. Such proceedings may include quasi-litigation, inter partes administrative proceedings in the U.S. Patent and Trademark Office, the European Patent Office and patent offices in other countries involving the Company’s intellectual property estate including certain in-licensed intellectual property. The outcome of any of the foregoing, is inherently uncertain. In addition, litigation and related matters are costly and may divert the attention of Company’s management and other resources that would otherwise be engaged in other activities. If the Company is unable to prevail in any such proceedings, the Company’s business, results of operations, liquidity and financial condition could be adversely affected.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

9. Commitments and Contingencies

Intellectual Property Agreements

Charpentier License Agreements

In April 2014, the Company entered into certain technology license agreements with Dr. Emmanuelle Charpentier pursuant to which the Company licensed certain intellectual property rights under joint ownership from Dr. Charpentier to develop and commercialize products for the treatment or prevention of human diseases. In connection therewith, Dr. Charpentier is entitled to receive nominal clinical milestone payments, low single digit percentage of sublicensing payments received under any sublicense agreement with a third party, and low single-digit percentage royalties based on annual net sales of licensed products and services by the Company and its affiliates and sublicensees. The Company paid an immaterial amount of fees to Dr. Charpentier under the Charpentier License Agreements.

Research, Manufacturing and License Agreements

The Company has engaged several research institutions and companies to identify new delivery strategies and applications of the Company’s gene editing technology. The Company is also a party to a number of license agreements which require significant upfront payments and may be required to make future royalty payments and potential milestone payments from time to time. In addition, the Company is also a party to intellectual property agreements, which require maintenance and milestone payments from time to time. Further, the Company is a party to a number of manufacturing agreements that require upfront payments for the future performance of services.

In association with these agreements, on a product-by-product basis, the counterparties are eligible to receive up to low eight-digit potential payments upon specified research, development and regulatory milestones. In addition, on a product-by-product basis, the counterparties are eligible to receive potential commercial milestone payments based on specified annual sales thresholds. The potential payments are low-single digit percentages of the specified annual sales thresholds. The counterparties are also eligible to receive low single-digit royalties on future net sales.

Under certain circumstances and if certain contingent future events occur, Vertex is eligible to receive up to $395.0 million in potential specified research, development, regulatory and commercial milestones and tiered single-digit percentage royalties on future net sales related to a specified target under an amendment to the 2015 Collaboration Agreement. Vertex also has the option to conduct research at their own cost in certain defined areas that, if beneficial to the CASGEVY program and ultimately achieves regulatory approval, then the Company could owe Vertex certain milestone payments aggregating to high eight digits, subject to certain limitations on the profitability of the CASGEVY program.

Under the A&R Vertex JDCA, the Company has an option to defer specified costs on the CASGEVY program in excess of $110.3 million for the years ended December 31, 2022, 2023 and 2024. The $110.3 million for 2023 does not include amounts attributable to our share of certain costs arising from a license agreement between Vertex and a third party, which we agreed to pay to Vertex upon the occurrence of an event specified in Amendment No. 1 to the A&R Vertex JDCA. In 2023 and 2022, the Company exercised its option to defer specified costs on the CASGEVY program in excess of the deferral limit under A&R Vertex JDCA. The Company deferred $80.9 million and $36.1 million of its share of costs incurred under the arrangement for the years ended December 31, 2023 and 2022, respectively, as spending on the CASGEVY program exceeded a specified amount. Any deferred amounts are only payable to Vertex as an offset against future profitability of the CASGEVY program and the amounts payable are capped at a specified maximum amount per year. These deferred costs on the CASGEVY program will be recognized by us when recoverability of such deferred amounts by Vertex is probable and the amount can be reasonably estimated. As of December 31, 2023 and 2022, no such deferred amounts have been recognized . Refer to Note 8 for further discussion on the Company’s arrangements with Vertex.

Litigation

In the ordinary course of business, the Company is from time to time involved in lawsuits, investigations, proceedings and threats of litigation related to, among other things, the Company’s intellectual property estate (including certain in-licensed intellectual property), commercial arrangements and other matters. Such proceedings may include quasi-litigation, inter partes administrative proceedings in the U.S. Patent and Trademark Office, the European Patent Office and patent offices in other countries involving the Company’s intellectual property estate including certain in-licensed intellectual property. The outcome of any of the foregoing, is inherently uncertain. In addition, litigation and related matters are costly and may divert the attention of Company’s management and other resources that would otherwise be engaged in other activities. If the Company is unable to prevail in any such proceedings, the Company’s business, results of operations, liquidity and financial condition could be adversely affected.