BLZE · Backblaze, Inc.

The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of restricted stock units. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $15.82 to $15.83, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein.

The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of restricted stock units. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $15.82 to $15.83, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein.

Represents previously issued restricted stock units that the Issuer retired for cash upon vesting in lieu of issuing shares of common stock.

These restricted stock units were settled by the Issuer at the closing price per share of the Issuer's common stock on the vesting date.

Represents previously issued restricted stock units that the Issuer retired for cash upon vesting in lieu of issuing shares of common stock.

These restricted stock units were settled by the Issuer at the closing price per share of the Issuer's common stock on the vesting date.

Pursuant to the Issuer's Director Compensation Policy, the Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU. The RSUs are subject to a service-based vesting requirement, which shall be satisfied on the earlier of (A) the date of the Issuer's next Annual Meeting of Stockholders, or (B) the one-year anniversary of the date of grant, provided that the Reporting Person remains in continuous service through such vesting date.

Pursuant to the Issuer's Director Compensation Policy, the Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU. The RSUs are subject to a service-based vesting requirement, which shall be satisfied on the earlier of (A) the date of the Issuer's next Annual Meeting of Stockholders, or (B) the one-year anniversary of the date of grant, provided that the Reporting Person remains in continuous service through such vesting date.

Pursuant to the Issuer's Director Compensation Policy, the Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU. The RSUs are subject to a service-based vesting requirement, which shall be satisfied on the earlier of (A) the date of the Issuer's next Annual Meeting of Stockholders, or (B) the one-year anniversary of the date of grant, provided that the Reporting Person remains in continuous service through such vesting date.

Pursuant to the Issuer's Director Compensation Policy, the Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU. The RSUs are subject to a service-based vesting requirement, which shall be satisfied on the earlier of (A) the date of the Issuer's next Annual Meeting of Stockholders, or (B) the one-year anniversary of the date of grant, provided that the Reporting Person remains in continuous service through such vesting date.

Represents previously issued restricted stock units that the Issuer retired for cash upon vesting in lieu of issuing shares of common stock.

These restricted stock units were settled by the Issuer at the closing price per share of the Issuer's common stock on the vesting date.

Represents previously issued restricted stock units that the Issuer retired for cash upon vesting in lieu of issuing shares of common stock.

These restricted stock units were settled by the Issuer at the closing price per share of the Issuer's common stock on the vesting date.

These shares of the Issuer's common stock were acquired pursuant to the Issuer's 2021 Employee Stock Purchase Plan ("ESPP") for the ESPP purchase period of November 20, 2025 through May 19, 2026. This transaction is exempt pursuant to Rule 16b-3(c) promulgated pursuant to the Securities Exchange Act of 1934.

Under the ESPP, the purchase price is equal to 85% of the lower of the closing price of the Issuer's common stock on the first day of the applicable purchase period or the purchase date. The closing price of the Issuer's common stock on November 20, 2025 was $4.33.

The Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A common stock for each RSU. The RSUs are subject to a service-based vesting requirement, which will vest on a quarterly basis over approximately 3 years with the first 1/12th tranche vesting on May 14, 2026, provided that the Reporting Person remains in continuous service through each such vesting date.

The Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A common stock for each RSU. The RSUs are subject to a service-based vesting requirement, which will vest on a quarterly basis over approximately 3 years with the first 1/12th tranche vesting on May 14, 2026, provided that the Reporting Person remains in continuous service through each such vesting date.

The Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU. The RSUs are subject to a service-based vesting requirement, and will vest 25% on the first anniversary of January 5, 2025 and the remainder in equal quarterly installments over the remaining 3 year period, provided that the Reporting Person remains in continuous service through each such vesting date. The RSUs were granted as an employment inducement award under the Company's 2024 New Employee Equity Incentive Plan in accordance with Nasdaq Listing Rule 5635(c)(4).

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the grant of RSUs referenced above. No shares were sold by the Reporting Person to satisfy this tax liability.

The Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive on share of Class A Common Stock for each RSU. The RSUs are fully vested.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the grant of RSUs referenced above. No shares were sold by the Reporting Person to satisfy this tax liability.

The Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive on share of Class A Common Stock for each RSU. The RSUs are fully vested.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of restricted stock units (RSUs). No shares were sold by the Reporting Person to satisfy this tax liability.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of restricted stock units (RSUs). No shares were sold by the Reporting Person to satisfy this tax liability.

Includes 2,500 shares of Class A Common Stock previously reported but not added to the total. The current total of 269,527 includes these 2,500 shares.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of Restricted Stock Units ("RSUs"). No shares were sold by the Reporting Person to satisfy this tax liability.

Includes 2,500 shares of Class of A Common Stock previously acquired under the Issuer's Employee Stock Purchase Plan on November 19, 2025.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of Restricted Stock Units ("RSUs"). No shares were sold by the Reporting Person to satisfy this tax liability.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of Restricted Stock Units ("RSUs"). No shares were sold by the Reporting Person to satisfy this tax liability.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of Restricted Stock Units ("RSUs"). No shares were sold by the Reporting Person to satisfy this tax liability.

Includes 2,500 shares of Class of A Common Stock previously acquired under the Issuer's Employee Stock Purchase Plan on May 19, 2025.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of Restricted Stock Units ("RSUs"). No shares were sold by the Reporting Person to satisfy this tax liability.

Pursuant to the Issuer's Director Compensation Policy, the Reporting Person was automatically granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU, in connection with the Issuer's Annual Meeting of Stockholders. The RSUs are subject to a service-based vesting requirement, which shall be satisfied on the earlier of (A) the date of the Issuer's next Annual Meeting of Stockholders, or (B) the one-year anniversary of May 27, 2025, provided that the Reporting Person remains in continuous service through such vesting date.

Pursuant to the Issuer's Director Compensation Policy, the Reporting Person was automatically granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU, in connection with the Issuer's Annual Meeting of Stockholders. The RSUs are subject to a service-based vesting requirement, which shall be satisfied on the earlier of (A) the date of the Issuer's next Annual Meeting of Stockholders, or (B) the one-year anniversary of May 27, 2025, provided that the Reporting Person remains in continuous service through such vesting date.

Pursuant to the Issuer's Director Compensation Policy, the Reporting Person was automatically granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU, in connection with the Issuer's Annual Meeting of Stockholders. The RSUs are subject to a service-based vesting requirement, which shall be satisfied on the earlier of (A) the date of the Issuer's next Annual Meeting of Stockholders, or (B) the one-year anniversary of May 27, 2025, provided that the Reporting Person remains in continuous service through such vesting date.

Pursuant to the Issuer's Director Compensation Policy, the Reporting Person was automatically granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU, in connection with the Issuer's Annual Meeting of Stockholders. The RSUs are subject to a service-based vesting requirement, which shall be satisfied on the earlier of (A) the date of the Issuer's next Annual Meeting of Stockholders, or (B) the one-year anniversary of May 27, 2025, provided that the Reporting Person remains in continuous service through such vesting date.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs"). No shares were sold by the Reporting Person to satisfy this tax liability.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of Restricted Stock Units ("RSUs"). No shares were sold by the Reporting Person to satisfy this tax liability.

The Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A common stock for each RSU. The RSUs are subject to a service-based vesting requirement, which will vest on a quarterly basis over approximately 3 years with the first 1/12th tranche vesting on May 20, 2025, provided that the Reporting Person remains in continuous service through each such vesting date.

The Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A common stock for each RSU. The RSUs are subject to a service-based vesting requirement, which will vest on a quarterly basis over approximately 3 years with the first 1/12th tranche vesting on May 20, 2025, provided that the Reporting Person remains in continuous service through each such vesting date.

The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of RSUs. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $6.22 to $6.405, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein.

The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of RSUs. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $6.22 to $6.405, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein.

The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of RSUs. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $6.22 to $6.405, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein.

The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of RSUs. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $6.465 to $6.805, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein.

The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of RSUs. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $6.465 to $6.805, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein.

The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of RSUs. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $6.465 to $6.805, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein.

The Reporting Person was granted RSUs, which represent a right to receive one share of Class A Common Stock for each RSU. The RSUs are fully vested.

The Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive on share of Class A Common Stock for each RSU. The RSUs are fully vested.

The Reporting Person was granted RSUs, which represent a contingent right to receive on share of Class A Common Stock for each RSU. The RSUs are fully vested.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs"). No shares were sold by the Reporting Person to satisfy this tax liability.

The shares of Class A Common Stock were withheld by the Issuer to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs"). No shares were sold by the Reporting Person to satisfy this tax liability.

The Reporting Person was granted restricted stock units ("RSUs"), which represent a contingent right to receive one share of Class A Common Stock for each RSU. The RSUs are subject to a service-based vesting requirement, and will vest 25% on the first anniversary of August 20, 2024 and the remainder in equal quarterly installments over the remaining 4 year period, provided that the Reporting Person remains in continuous service through each such vesting date. The RSUs were granted as a employment inducement award under the Company's 2024 New Employee Equity Incentive Plan in accordance with Nasdaq Listing Rule 5635(c)(4).