Equity Method Investment	9 Months Ended
Sep. 30, 2022
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investment	8. Equity method investment Orbital In September 2022, the Company entered into a License and Research Collaboration Agreement, or the Orbital Agreement, with Orbital Therapeutics, Inc., or Orbital, a newly formed entity, focused on advancing non-viral delivery and RNA technologies (See Note 11). In exchange for contributing exclusive and non-exclusive licenses and certain services, the Company received a 31.5% fully diluted equity interest in Orbital at the time of closing pursuant to a Common Stock Issuance Agreement, or the Orbital Issuance Agreement, as well as certain exclusive and non-exclusive licenses from Orbital. As of the closing date Beam held 97.0% of the outstanding common stock of Orbital. Additionally, certain members of the Company's executive team are providing interim management services to Orbital under separate agreements between Orbital and the executives. Orbital is not compensating the Company for the interim management services. The Company has significant influence over, but does not control, Orbital through its noncontrolling representation on Orbital’s board of directors and the Company’s equity interest in Orbital. The Company determined that Orbital is a variable interest entity because it does not have sufficient equity at risk to finance its operations without additional subordinated financial support. The Company is not the primary beneficiary as it does not have the power to direct activities that most significantly impact Orbital’s economic performance. Accordingly, the Company does not consolidate the financial statements of Orbital and accounts for its investment using the equity method of accounting. As of the closing date, the fair value of the Company’s investment in Orbital was $25.5 million, which represents the fair value of the common stock received under the Orbital Issuance Agreement (See Note 11). The fair value of the Orbital common stock was determined by management with the assistance of a third-party valuation specialist. In determining the fair value of the Company’s investment, the valuation specialist used an option pricing model backsolve approach based on Orbital's most recent funding of preferred stock. The valuation requires the input of certain subjective assumptions. The key assumptions used in the option pricing model, which are level 3 inputs, include the anticipated holding period to an exit and liquidity event, the volatility of market participants (68%) and the discount for lack of marketability (43%). After its initial investment, the Company will adjust the carrying value of its investment in Orbital by its proportionate share of Orbital’s net loss based on the Company’s share, of Orbital’s outstanding common stock and in-substance common stock. At the date of the investment, a basis difference was identified as the carrying value of the Company’s investment in Orbital exceeded the Company’s proportionate share of the underlying net assets in Orbital. The Company concluded that the basis difference was primarily attributable to Orbital’s IPR&D assets. As Orbital did not meet the definition of a business due to substantially all of the estimated fair value of the gross assets being concentrated in the group of similar IPR&D assets, the basis difference attributable to the IPR&D with no alternative future use was immediately expensed as of the date of the investment. The Company’s proportionate share of the basis difference exceeded its carrying value of the equity method investment in Orbital and the equity investment balance was reduced to zero. There is no commitment for the Company to provide financial support to Orbital, and therefore the carrying value of the equity method investment will not be reduced below zero. For the three and nine months ended September 30, 2022, the Company recognized a loss from its equity method investment of $25.5 million in association with the basis difference charge in the Company’s condensed consolidated statements of operations. The maximum exposure to loss is limited to the Company’s equity investment in Orbital, which has a carrying value of zero at September 30, 2022. To date the Company has not received any dividends from Orbital.

Equity Method Investment

9 Months Ended

Sep. 30, 2022

Equity Method Investments and Joint Ventures [Abstract]

8. Equity method investment

Orbital

In September 2022, the Company entered into a License and Research Collaboration Agreement, or the Orbital Agreement, with Orbital Therapeutics, Inc., or Orbital, a newly formed entity, focused on advancing non-viral delivery and RNA technologies (See Note 11). In exchange for contributing exclusive and non-exclusive licenses and certain services, the Company received a 31.5% fully diluted equity interest in Orbital at the time of closing pursuant to a Common Stock Issuance Agreement, or the Orbital Issuance Agreement, as well as certain exclusive and non-exclusive licenses from Orbital. As of the closing date Beam held 97.0% of the outstanding common stock of Orbital. Additionally, certain members of the Company's executive team are providing interim management services to Orbital under separate agreements between Orbital and the executives. Orbital is not compensating the Company for the interim management services.

The Company has significant influence over, but does not control, Orbital through its noncontrolling representation on Orbital’s board of directors and the Company’s equity interest in Orbital. The Company determined that Orbital is a variable interest entity because it does not have sufficient equity at risk to finance its operations without additional subordinated financial support. The Company is not the primary beneficiary as it does not have the power to direct activities that most significantly impact Orbital’s economic performance. Accordingly, the Company does not consolidate the financial statements of Orbital and accounts for its investment using the equity method of accounting.

As of the closing date, the fair value of the Company’s investment in Orbital was $25.5 million, which represents the fair value of the common stock received under the Orbital Issuance Agreement (See Note 11). The fair value of the Orbital common stock was determined by management with the assistance of a third-party valuation specialist. In determining the fair value of the Company’s investment, the valuation specialist used an option pricing model backsolve approach based on Orbital's most recent funding of preferred stock. The valuation requires the input of certain subjective assumptions. The key assumptions used in the option pricing model, which are level 3 inputs, include the anticipated holding period to an exit and liquidity event, the volatility of market participants (68%) and the discount for lack of marketability (43%). After its initial investment, the Company will adjust the carrying value of its investment in Orbital by its proportionate share of Orbital’s net loss based on the Company’s share, of Orbital’s outstanding common stock and in-substance common stock.

At the date of the investment, a basis difference was identified as the carrying value of the Company’s investment in Orbital exceeded the Company’s proportionate share of the underlying net assets in Orbital. The Company concluded that the basis difference was primarily attributable to Orbital’s IPR&D assets. As Orbital did not meet the definition of a business due to substantially all of the estimated fair value of the gross assets being concentrated in the group of similar IPR&D assets, the basis difference attributable to the IPR&D with no alternative future use was immediately expensed as of the date of the investment. The Company’s proportionate share of the basis difference exceeded its carrying value of the equity method investment in Orbital and the equity investment balance was reduced to zero. There is no commitment for the Company to provide financial support to Orbital, and therefore the carrying value of the equity method investment will not be reduced below zero. For the three and nine months ended September 30, 2022, the Company

recognized a loss from its equity method investment of $25.5 million in association with the basis difference charge in the Company’s condensed consolidated statements of operations.

The maximum exposure to loss is limited to the Company’s equity investment in Orbital, which has a carrying value of zero at September 30, 2022. To date the Company has not received any dividends from Orbital.