Fair Value of Financial Instruments

9 Months Ended

Sep. 30, 2021

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

4. Fair Value of Financial Instruments

Financial instruments reported at fair value on a recurring basis include cash equivalents and marketable securities. The following tables present the fair value of cash equivalents and marketable securities in accordance with the hierarchy discussed in Note 2 (in thousands): 

	Quoted		Significant
	prices		other		Significant
	in active		observable		unobservable
	markets		inputs		inputs
	(Level 1)		(Level 2)		(Level 3)		Total
September 30, 2021
Cash equivalents:
Money market mutual funds	$	—	$	187,123	$	—	$	187,123
Total cash equivalents		—		187,123		—		187,123
Marketable securities:
U.S. government and federal agency securities		—		24,980		—		24,980
Certificates of deposit		—		2,948		—		2,948
Corporate bonds		—		274,181		—		274,181
Municipal securities		—		3,004		—		3,004
Total marketable securities		—		305,113		—		305,113
Total cash equivalents and marketable securities	$	—	$	492,236	$	—	$	492,236

	Quoted		Significant
	prices		other		Significant
	in active		observable		unobservable
	markets		inputs		inputs
	(Level 1)		(Level 2)		(Level 3)		Total
December 31, 2020
Cash equivalents:
Money market mutual funds	$	—	$	96,307	$	—	$	96,307
Total cash equivalents		—		96,307		—		96,307
Marketable securities:
U.S. government and federal agency securities		—		12,804		—		12,804
Certificates of deposit		—		1,990		—		1,990
Corporate bonds		—		166,292		—		166,292
Municipal securities		—		3,037		—		3,037
Total marketable securities		—		184,123		—		184,123
Total cash equivalents and marketable securities	$	—	$	280,430	$	—	$	280,430

Management estimates that the carrying amounts of its current accounts receivable, accounts payable and accrued expenses and other current liabilities approximate fair value due to the short-term nature of those instruments. Accounts receivable which contain non-current portions are recorded at their present values using a discount rate that is based on prevailing market rates and the credit profile of the licensee on the date the amounts are initially recorded. Management does not believe there have been any significant changes in market conditions or credit quality that would cause the discount rates initially used to be materially different from those that would be used as of September 30, 2021 to determine the present value of the receivables. Accordingly, management estimates that the carrying value of its non-current accounts receivable approximates the fair value of those instruments.

Non-marketable Equity Securities

Non-marketable equity securities are measured at cost less impairment, adjusted for observable price changes for identical or similar investments of the same issuer. As of September 30, 2021, the Company did not hold any non-marketable equity securities. As of December 31, 2020, non-marketable equity securities had a carrying value of $1.1 million and were included in other assets on the consolidated balance sheet. The Company did not identify any observable price changes or changes in circumstances that would have had an adverse effect on the fair value of the securities as of December 31, 2020. No remeasurements or impairment losses were recorded on non-marketable equity securities during the three and nine months ended September 30, 2021 and 2020.

The Company’s non-marketable equity securities as of December 31, 2020 consisted solely of equity securities of Corlieve Therapeutics SAS (Corlieve), which were acquired in June 2020 as consideration under a license and collaboration agreement with Corlieve. In July 2021, Corlieve was acquired by uniQure N.V. (uniQure). In exchange for its ownership in Corlieve, the Company received proceeds of €4.8 million ($5.6 million) from uniQure and is entitled to receive additional proceeds of €0.6 million ($0.6 million as of September 30, 2021) by July 2022. During the three and nine months ended September 30, 2021, the Company recorded a realized gain of $5.2 million as a result of the acquisition of its Corlieve securities by uniQure, which is included in investment income (loss) in the consolidated statements of operations and comprehensive income (loss). In connection with the acquisition, the Company is also eligible to receive payments of up to €37.1 million ($43.2 million as of September 30, 2021) from uniQure contingent upon the achievement of various development and regulatory milestones, none of which have been recognized in the consolidated financial statements as of September 30, 2021. Proceeds contingent upon the achievement of these milestones will be recognized as investment income in the period in which any uncertainty regarding realization is substantially resolved, which may not occur until the achievement of the underlying milestones. It is at least reasonably possible that some or all of the proceeds contingent upon these milestones will not be realized by the Company.