Related Parties	12 Months Ended
Dec. 31, 2020
Related Party Transactions [Abstract]
Related Parties	Note 13. Related parties Relationship and transactions with Gilead Sciences, Inc. (Gilead) As of December 31, 2020, Gilead held approximately 13% of the Company’s outstanding common stock. These holdings resulted from Gilead’s investment in the Company of approximately $56.7 million, net of offering costs, by purchasing 2,200,000 shares of common stock at a per share price of $27.50 in the May 2020 Public Offering as well as Gilead’s acquisition of 5,963,029 shares under the Stock Purchase Agreement. Gilead has the right, at its option, to purchase up to a maximum of 35% of the Company’s then-outstanding voting common stock, from time to time over the next five years. Gilead also has the right under the Investor Rights Agreement to designate two individuals to be appointed to the Company’s board of directors. The Company appointed the first Gilead designee, Merdad Parsey, M.D., Ph.D. and Michael Quigley, Ph.D., to its board of directors pursuant to the Investor Rights Agreement. See Note 7 for further discussion of the agreements with Gilead. At December 31, 2020, the Company had a $0.9 million cost sharing receivable recorded on the consolidated balance sheets under receivable from collaboration partners, to be invoiced the following quarter. The Company also had $185.4 million in deferred revenue at December 31, 2020, of which $117.8 million represented the long-term portion of deferred revenue allocated to performance obligations not expected to be completed within one year of the balance sheet date, which was recorded in deferred revenue, noncurrent on the consolidated balance sheets. The Company also recognized $9.7 million in contract liabilities for future development and commercialization services which Gilead prepaid, all of which was recorded in other long-term liabilities on the consolidated balance sheets. For the year ended December 31, 2020, the Company recognized $70.5 million in revenue under the Gilead Collaboration Agreement. The Company also recognized a $3.4 million reduction in research and development expense related to its cost-sharing provisions of the agreement. The Company received $175 million in upfront payments from Gilead in connection with the Option, License and Collaboration Agreement and identified $100 million in unconstrained consideration to be received in 2022. In addition, the Company received $200 million from Gilead in connection with the Stock Purchase Agreement, of which approximately $109.4 million represented the fair value of stock purchased at the transaction closing date in July 2020 with the remaining premium of $90.6 million allocated to the transaction price.

Related Parties

12 Months Ended

Dec. 31, 2020

Note 13. Related parties

Relationship and transactions with Gilead Sciences, Inc. (Gilead)

As of December 31, 2020, Gilead held approximately 13% of the Company’s outstanding common stock. These holdings resulted from Gilead’s investment in the Company of approximately $56.7 million, net of offering costs, by purchasing 2,200,000 shares of common stock at a per share price of $27.50 in the May 2020 Public Offering as well as Gilead’s acquisition of 5,963,029 shares under the Stock Purchase Agreement. Gilead has the right, at its option, to purchase up to a maximum of 35% of the Company’s then-outstanding voting common stock, from time to time over the next five years. Gilead also has the right under the Investor Rights Agreement to designate two individuals to be appointed to the Company’s board of directors. The Company appointed the first Gilead designee, Merdad Parsey, M.D., Ph.D. and Michael Quigley, Ph.D., to its board of directors pursuant to the Investor Rights Agreement. See Note 7 for further discussion of the agreements with Gilead.

At December 31, 2020, the Company had a $0.9 million cost sharing receivable recorded on the consolidated balance sheets under receivable from collaboration partners, to be invoiced the following quarter. The Company also had $185.4 million in deferred revenue at December 31, 2020, of which $117.8 million represented the long-term portion of deferred revenue allocated to performance obligations not expected to be completed within one year of the balance sheet date, which was recorded in deferred revenue, noncurrent on the consolidated balance sheets. The Company also recognized $9.7 million in contract liabilities for future development and commercialization services which Gilead prepaid, all of which was recorded in other long-term liabilities on the consolidated balance sheets.

For the year ended December 31, 2020, the Company recognized $70.5 million in revenue under the Gilead Collaboration Agreement. The Company also recognized a $3.4 million reduction in research and development expense related to its cost-sharing provisions of the agreement.

The Company received $175 million in upfront payments from Gilead in connection with the Option, License and Collaboration Agreement and identified $100 million in unconstrained consideration to be received in 2022. In addition, the Company received $200 million from Gilead in connection with the Stock Purchase Agreement, of which approximately $109.4 million represented the fair value of stock purchased at the transaction closing date in July 2020 with the remaining premium of $90.6 million allocated to the transaction price.