8.	Related Party Transactions

Caribou Therapeutics

In July 2014, the Company issued Caribou Therapeutics Holdco, LLC, a wholly-owned subsidiary of Caribou, 8,110,599 Junior Preferred Units. As a result of this and related transactions, Caribou owned 9.3 percent of the Company’s voting interests as of March 31, 2018.

The Company recognized general and administrative expense of $0.2 million during the three months ended March 31, 2018, and a de minimis amount during the three months ended March 31, 2017, related to the Company’s obligation to pay 30.0 percent of Caribou’s patent prosecution, filing and maintenance costs.

Novartis Institutes for BioMedical Research

In connection with its entry into the collaboration and license agreement and related equity transactions with Novartis, the Company issued Novartis 4,761,905 Class A-1 Preferred Units and 2,666,666 Class A-2 Preferred Units. In August 2015, Novartis acquired 761,905 shares of the Company’s Series B Preferred Stock, and in May 2016, Novartis acquired 277,777 shares of the Company’s common stock in a private placement transaction concurrent with the Company’s IPO. As a result of these and subsequent transactions, Novartis collectively owned 9.9% of the Company’s voting interests as of March 31, 2018.

The Company recognized collaboration revenue of $2.4 million and $2.2 million during the three months ended March 31, 2018 and 2017, respectively, in the consolidated statements of operations related to this agreement. As of March 31, 2018 and December 31, 2017, the Company had recorded accounts receivable of $1.0 million and $6.0 million and deferred revenue of $4.4 million and $11.2 million, respectively, related to this collaboration. Refer to Note 5, Collaborations, for additional information regarding this collaboration agreement.