Sutro Biopharma, Inc. Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Basis of Presentation and Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Cash Equivalents and Marketable Securities - Schedule of Cash Equivalents and Marketable Securities (Details)

v3.22.0.1

Cash Equivalents and Marketable Securities - Schedule of Cash Equivalents and Marketable Securities (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	$ 228,883,000	$ 324,845,000
Unrealized Gains		131,000
Unrealized Losses	(314,000)	(3,000)
Fair Value	228,569,000	324,973,000
Less amounts classified as cash equivalents, Amortized Cost Basis	(30,414,000)	(206,152,000)	$ (4,960,000)
Marketable Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	199,432,000	120,213,000
Unrealized Gains		131,000
Unrealized Losses	(314,000)	(3,000)
Fair Value	199,118,000	120,341,000
Cash Equivalents
Cash And Cash Equivalents [Line Items]
Less amounts classified as cash equivalents, Amortized Cost Basis	(29,451,000)	(204,632,000)
Less amounts classified as cash equivalents, Fair Value	(29,451,000)	(204,632,000)
Money Market Funds
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	29,451,000	204,632,000
Fair Value	29,451,000	204,632,000
Commercial Paper
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	22,580,000	42,208,000
Fair Value	22,580,000	42,208,000
Corporate Debt Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	75,012,000	25,669,000
Unrealized Gains		48,000
Unrealized Losses	(151,000)	(1,000)
Fair Value	74,861,000	25,716,000
Asset-backed Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	32,975,000	12,593,000
Unrealized Gains		39,000
Unrealized Losses	(18,000)
Fair Value	32,957,000	12,632,000
U.S. Government Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	47,504,000	39,743,000
Unrealized Gains		44,000
Unrealized Losses	(84,000)	(2,000)
Fair Value	47,420,000	$ 39,785,000
Supranational Debt Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	21,361,000
Unrealized Losses	(61,000)
Fair Value	$ 21,300,000

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