Company: IMRX
Filing Date: 2025-09-08
Form Type: 424B3
Source: 0001104659-25-088317
Chunk: 21

Company: Immuneering Corp
Filing Date: 2025-09-08
Form: 424B3
Chunk 21
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#### Trading Symbol and Market
Our Class A common stock is listed on the Nasdaq Global Market under the symbol “IMRX.”

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TABLE OF CONTENTS

### PRIVATE PLACEMENT OF SECURITIES
On August 21, 2025, the Company entered into a Securities Purchase Agreement (the “Purchase Agreement”) with the purchasers party thereto (the “Investors”), pursuant to which the Company agreed to sell securities to the Investors in a private placement (the “Private Placement”). The Purchase Agreement provided for the sale and issuance by the Company of: (i) an aggregate of 6,329,113 shares (the “Shares”) of the Company’s Class A common stock (or, for certain investors in lieu of Class A common stock, pre-funded warrants to purchase shares of Class A common stock (the “Pre-Funded Warrants”), with an exercise price of $0.001 per share), and (ii) accompanying warrants to purchase up to 2,848,096 shares of Class A common stock (the “Purchase Warrants”), with an exercise price of $5.50 per share, for aggregate gross proceeds of approximately $25.0 million, before deducting private placement expenses. Each Share (or Pre-Funded Warrant to purchase one share) was issued with an accompanying Purchase Warrant to purchase 45% of one share, and the combined effective purchase price per Share (or Pre-Funded Warrant to purchase one share) and accompanying Purchase Warrant to purchase 45% of one share was $3.95 (less the exercise price of the Pre-Funded Warrant, if applicable).

Each of the Investors is party to a confidentiality agreement with the Company, pursuant to which the Company has disclosed certain information to such Investors. Pursuant to the terms of the Purchase Agreement, each Investor has agreed, severally and not jointly, that neither it nor any affiliate acting on its behalf will execute any purchases or sales of any of the Company’s securities during the period commencing on August 21, 2025 and ending at such time that the Company files a Current Report on Form 8-K (on or prior to November 30, 2025) disclosing such information previously disclosed to such Investor.

The closing of the Private Placement occurred on August 26, 2025 (the “Closing Date”).

The Pre-Funded Warrants are immediately exercisable until exercised in full, subject to the Beneficial Ownership Limitation (as described below).

The