Sutro Biopharma, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

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

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

v3.21.2

Cash Equivalents and Marketable Securities - Schedule of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	$ 253,648	$ 324,845
Unrealized Gains	16	131
Unrealized (Losses)	(46)	(3)
Fair Value	253,618	324,973
Less amounts classified as cash equivalents, Amortized Cost Basis	(30,707)	(206,152)	$ (64,370)
Marketable Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	223,540	120,213
Unrealized Gains	16	131
Unrealized (Losses)	(46)	(3)
Fair Value	223,510	120,341
Cash Equivalents
Cash And Cash Equivalents [Line Items]
Less amounts classified as cash equivalents, Amortized Cost Basis	(30,108)	(204,632)
Less amounts classified as cash equivalents, Fair Value	(30,108)	(204,632)
Money Market Funds
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	30,108	204,632
Unrealized Gains	0	0
Unrealized (Losses)	0	0
Fair Value	30,108	204,632
Commercial Paper
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	56,568	42,208
Unrealized Gains	0	0
Unrealized (Losses)	0	0
Fair Value	56,568	42,208
Corporate Debt Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	70,290	25,669
Unrealized Gains	7	48
Unrealized (Losses)	(21)	(1)
Fair Value	70,276	25,716
Asset-backed Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	37,607	12,593
Unrealized Gains	2	39
Unrealized (Losses)	(14)	0
Fair Value	37,595	12,632
U.S. Government Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	37,624	39,743
Unrealized Gains	7	44
Unrealized (Losses)	0	(2)
Fair Value	37,631	$ 39,785
Supranational Debt Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	21,451
Unrealized Gains	0
Unrealized (Losses)	(11)
Fair Value	$ 21,440

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