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

Stockholders' Equity - Additional Information (Details)

v3.21.2

Stockholders' Equity - Additional Information (Details) - $ / shares		1 Months Ended	9 Months Ended
	Oct. 01, 2018	Aug. 31, 2017	Sep. 30, 2021	Dec. 31, 2020	Feb. 28, 2020
Stockholders Equity [Line Items]
Voting rights per share			one vote per share
Preferred stock shares authorized			10,000,000	10,000,000
Preferred stock, par value			$ 0.001	$ 0.001
Preferred stock, outstanding			0	0
Loan and Security Agreement \| Oxford Finance LLC
Stockholders Equity [Line Items]
Issuance of warrants to purchase shares					54,171
Loan and Security Agreement \| Silicon Valley Bank
Stockholders Equity [Line Items]
Issuance of warrants to purchase shares					27,086
Loan and Security Agreement \| Oxford Finance LLC and Silicon Valley Bank
Stockholders Equity [Line Items]
Issuance of warrants to purchase shares					81,257
Exercise price per share					$ 9.23
Series E Redeemable Convertible Preferred Stock
Stockholders Equity [Line Items]
Issuance of warrants to purchase shares	46,359
Preferred stock, conversion basis	1-for-0.0275
Series C Redeemable Convertible Preferred Stock
Stockholders Equity [Line Items]
Issuance of warrants to purchase shares	25,454
Preferred stock, conversion basis	1-for-0.0370
Cancellation of redeemable convertible preferred warrants	1,232,220
Conversion of warrants to purchase of shares of common stock	687,928
Oxford Finance LLC and Silicon Valley Bank \| Series D Two Redeemable Convertible Preferred Stock \| Loan and Security Agreement
Stockholders Equity [Line Items]
Issuance of warrants to purchase shares		682,230
Exercise price per share		$ 0.6596
Oxford Finance LLC and Silicon Valley Bank \| Series E Redeemable Convertible Preferred Stock \| Loan and Security Agreement
Stockholders Equity [Line Items]
Issuance of warrants to purchase shares		1,682,871
Exercise price per share		$ 0.2674
Term of warrant exercisable		10 years

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