X0306 4 2021-05-17 false 0001459839 SI-BONE, Inc. SIBN 0001754765 Pisetsky Michael A C/O SI-BONE, INC. 471 EL CAMINO REAL, SUITE 101 SANTA CLARA CA 95050 false true false false GC & Chief Compliance Officer Common Stock 2021-05-17 4 S false 1008.00 31.4016 D 78420.00 D Common Stock 2021-05-17 4 S false 894.00 31.4016 D 77526.00 D Common Stock 2021-05-18 4 M false 1975.00 4.32 A 79501.00 D Common Stock 2021-05-18 4 S false 1975.00 32.00 D 79036.00 D Stock Option (Right to Buy) 4.32 2021-05-18 4 M false 1975.00 0.00 D 2026-07-26 Common Stock 1975.00 12938.00 D The sale reported on this Form 4 represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of restricted stock units. The sale satisfies the tax withholding obligations to be funded by a "sell to cover" transaction and does not represent a discretionary trade by the Reporting Person. The sale reported on this Form 4 was effected pursuant to a 10b5-1 trading plan. Includes 1,510 shares acquired under the SI-BONE, Inc. 2018 Employee Stock Purchase Plan on May 17, 2021. Includes 57,434 shares issuable on the settlement of restricted stock units granted to the Reporting Person. Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock. The shares subject to the option vest in equal monthly installments over four years commencing on vesting commencement date, subject to Reporting Person's continued service through each relevant vesting date. /s/ Michael A. Pisetsky 2021-05-19