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

Equity Incentive Plans, Equity Inducement Plans, Employee Stock Purchase Plan and Stock-Based Compensation - Summary of Option Activity (Details)

v3.23.1

Equity Incentive Plans, Equity Inducement Plans, Employee Stock Purchase Plan and Stock-Based Compensation - Summary of Option Activity (Details) - 2004 Plan, 2018 Plan and 2021 Plan	3 Months Ended
	Mar. 31, 2023 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options outstanding, Beginning Balance, Shares \| shares	7,310,611
Granted, Shares \| shares	1,118,000
Exercised, Shares \| shares	(53,060)
Canceled and forfeited, Shares \| shares	(38,952)
Stock options outstanding, Ending Balance, Shares \| shares	8,336,599
Stock options exercisable, Shares \| shares	5,386,257
Stock options outstanding, Weighted - Average Exercise Price, Beginning Balance \| $ / shares	$ 12.68
Weighted - Average Exercise Price, Granted \| $ / shares	5.78
Weighted - Average Exercise Price, Exercised \| $ / shares	5.92
Weighted - Average Exercise Price, Canceled and forfeited \| $ / shares	12.35
Stock options outstanding, Weighted - Average Exercise Price, Ending Balance \| $ / shares	11.80
Stock options exercisable, Weighted - Average Exercise Price, Exercisable \| $ / shares	$ 13.04

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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