UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Caribou Biosciences, Inc.

(Exact name of Registrant as Specified in Its Charter)

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 1.01 Entry into a Material Definitive Agreement.

On August 9, 2022, Caribou Biosciences, Inc., a Delaware corporation (the “Company”), entered into an Open Market Sale AgreementSM (the “Sales Agreement”) with Jefferies LLC (“Jefferies”) with respect to an “at the market offering” program, under which the Company may, from time to time, in its sole discretion, issue and sell through Jefferies, acting as sales agent, up to $100.0 million of the Company’s shares of common stock, par value $0.0001 per share (the “Shares”).

The issuance and sale, if any, of the Shares by the Company under the Sales Agreement is subject to the effectiveness of the Company’s registration statement on Form S-3 (File No. 333-266712) (the “Registration Statement”), filed with the Securities and Exchange Commission on August 9, 2022.

Pursuant to the Sales Agreement, Jefferies may sell the Shares by any method permitted by law deemed to be an “at the market offering” as defined in Rule 415(a)(4) of the Securities Act of 1933, as amended (the “Securities Act”). Jefferies will use commercially reasonable efforts consistent with its normal sales and trading practices to sell the Shares from time to time, based upon instructions from the Company (including any price or size limits or other customary parameters or conditions the Company may impose).

The Company will pay Jefferies a commission equal to 3.0% of the aggregate gross proceeds of any Shares sold through Jefferies pursuant to the Sales Agreement.

The Company is not obligated to sell any Shares under the Sales Agreement. The offering of the Shares pursuant to the Sales Agreement will terminate upon the earlier to occur of (i) the sale of all Shares subject to the Sales Agreement and (ii) the termination of the Sales Agreement as permitted therein.

The Sales Agreement contains representations, warranties, and covenants that are customary for transactions of this type. In addition, the Company has agreed to indemnify Jefferies against certain civil liabilities, including liabilities under the Securities Act.

The foregoing description of the Sales Agreement is not complete and is qualified in its entirety by reference to the full text of the Sales Agreement, a copy of which is filed as Exhibit 10.1 to this Current Report on Form 8-K and is incorporated herein by reference.

This Current Report on Form 8-K shall not constitute an offer to sell or the solicitation of an offer to buy the securities discussed herein, nor shall there be any offer, solicitation, or sale of the securities in any jurisdiction in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.