Material Event (Form 8-K)

On May 12, 2025, Sangamo Therapeutics, Inc. ("Sangamo" or the "Company") entered into an underwriting agreement (the "Underwriting Agreement") with Cantor Fitzgerald & Co., as representative of the several underwriters named therein (collectively, the "Underwriters"), relating to the issuance and sale (the "Offering") of 12,235,000 shares of the Company's common stock, par value $0.01 per share (the "Common Stock"), and pre-funded warrants to purchase 34,398,393 shares of Common Stock (the "Pre-Funded Warrants"), together with accompanying warrants to purchase 46,633,393 shares of Common Stock (the "Purchase Warrants" and together with the Pre-Funded Warrants, the "Warrants"). The combined offering price of each share of Common Stock and accompanying Purchase Warrant is $0.50. The combined offering price of each Pre-Funded Warrant and accompanying Purchase Warrant is $0.49. The Common Stock and Pre-Funded Warrants are being sold in combination with an accompanying Purchase Warrant to purchase one share of Common Stock issued for each share of Common Stock or Pre-Funded Warrant sold. All of the securities in the Offering are being sold by the Company. The gross proceeds to the Company from the Offering, before deducting underwriting discounts and estimated offering expenses, is expected to be approximately $23.0 million. The Offering is expected to close on May 14, 2025, subject to satisfaction of customary closing conditions.

Each Purchase Warrant will have an initial exercise price per share of $0.75, subject to certain adjustments. The Purchase Warrants will be exercisable six months after the date of issuance and may be exercised thereafter at any time until expiration six years after the date of issuance. A holder (together with its affiliates and other attribution parties) may not exercise any portion of a Purchase Warrant to the extent that immediately prior to or after giving effect to such exercise the holder would own more than 4.99% of the Company's outstanding Common Stock immediately after exercise, which percentage may be changed at the holder's election to a lower or higher percentage not in excess of 19.99% (if exceeding such percentage would result in a change of control under Nasdaq Listing Rule 5635(b) or any successor rule) upon 61 days' notice to the Company subject to the terms of the Purchase Warrants. Subject to the satisfaction of customary equity conditions as described in the Purchase Warrants, including the 4.99% exercise limitation, at Sangamo's option after six months from the date of issuance, Sangamo may force the exercise of the Purchase Warrants at any time the weighted-average price of the Common Stock exceeds $2.75 (as adjusted for stock splits, stock dividends, recapitalizations and similar events) for a period of ten consecutive trading days.

The Offering is being made pursuant to Sangamo's effective registration statement on Form S-3 (Registration Statement No. 333-283179) previously filed with the Securities and Exchange Commission (the "SEC") and a prospectus supplement thereunder.

The Underwriting Agreement contains customary representations, warranties and agreements by the Company, customary conditions to closing, indemnification obligations of the Company and the Underwriters, including for liabilities arising under the Securities Act of 1933, as amended, other obligations of the parties and termination provisions. The representations, warranties and covenants contained in the Underwriting Agreement were made only for the purposes of such agreement and as of specific dates, and were solely for the benefit of the parties to such agreement.

The foregoing descriptions of the terms of the Underwriting Agreement and Warrants are each qualified in their entirety by reference to the Underwriting Agreement, form of Pre-Funded Warrant and form of Purchase Warrant, respectively, which are attached as Exhibit 1.1, Exhibit 4.1 and Exhibit 4.2 hereto, respectively, and incorporated by reference herein.

A copy of the legal opinion of Cooley LLP relating to the validity of the issuance and sale of the securities in the Offering is attached as Exhibit 5.1 hereto.