8-K

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

Date of Report (Date of earliest event reported): November 24, 2023

Harpoon Therapeutics, Inc.

(Exact name of Registrant as Specified in Its Charter)

Delaware	001-38800	47-3458693
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(IRS Employer Identification No.)

611 Gateway Boulevard, Suite 400 South San Francisco, California	94080
(Address of Principal Executive Offices)	(Zip Code)

(650) 443-7400

(Registrant’s Telephone Number, Including Area Code)

Not Applicable

(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 (see General Instructions A.2. below):

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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

Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common stock, par value $0.0001 per share	HARP	The Nasdaq Stock Market LLC

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 8.01 Other Events.

On March 13, 2020, Harpoon Therapeutics, Inc. (the “Company”) entered into an at-the-market issuance sales agreement (the “Agreement”) with Cantor Fitzgerald & Co. (“Cantor Fitzgerald”) under which the Company may offer and sell, from time to time at its sole discretion, shares of its common stock, par value $0.0001 per share (the “Common Stock”), through Cantor Fitzgerald as its sales agent.

On April 21, 2023, the Company filed a registration statement on Form S-3 (Registration No. 333-272064), which became effective on May 15, 2023, including a prospectus offering up to $8,500,000 of shares of its Common Stock in accordance with the Agreement (the “Current Prospectus”). The amount registered under the Current Prospectus was, as of the filing date, subject to limitations imposed by General Instruction I.B.6. of Form S-3. As of October 26, 2023, the Company is no longer subject to General Instruction I.B.6. of Form S-3. On November 24, 2023, the Company filed Amendment No. 1 to the Current Prospectus (“Amendment No. 1”) to increase the offering to $59,086,211 of shares of its Common Stock.

The purpose of this Current Report on Form 8-K is to file an opinion in connection with the increase in the size of the offering pursuant to Amendment No. 1 to the Current Prospectus. A copy of the opinion of Cooley LLP relating to the legality of the shares of Common Stock that may be issued pursuant to the Agreement and Current Prospectus, as amended by Amendment No. 1, is attached as Exhibit 5.1 to this Current Report on Form 8-K.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.	Description
5.1	Opinion of Cooley LLP.
23.1	Consent of Cooley LLP (included in Exhibit 5.1).
104	Cover Page Interactive Data File (embedded within the Inline XBRL document).

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 hereunto duly authorized.

	Harpoon Therapeutics, Inc.
Date: November 24, 2023	By:	/s/ Julie Eastland
		Julie Eastland
		President and Chief Executive Officer

EX-5.1

Exhibit 5.1

Courtney M.W. Tygesson

+1 312 881 6680

ctygesson@cooley.com

November 24, 2023

Harpoon Therapeutics, Inc.

611 Gateway Boulevard, Suite 400

South San Francisco, California 94080

Ladies and Gentlemen:

We have acted as counsel to Harpoon Therapeutics, Inc., a Delaware corporation (the “Company”), in connection with the offering by the Company of shares of the Company’s common stock, $0.0001 par value per share (the “Common Stock”), having aggregate sale proceeds of up to $59,086,211 (the “Shares”), pursuant to a Registration Statement on Form S-3 (File No. 333-271400) (the “Registration Statement”) filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”), the prospectus included in the Registration Statement (the “Base Prospectus”) and the amendment to the prospectus relating to the Shares dated November 24, 2023, to be filed with the Commission pursuant to Rule 424(b) under the Act (together with the Base Prospectus, the “Prospectus”). The Shares are to be sold by the Company in accordance with that certain Controlled Equity Offering^SM Sales Agreement, dated March 13, 2020, by and between the Company and Cantor Fitzgerald & Co. (the “Agreement”), as described in the Prospectus.

In connection with this opinion, we have examined and relied upon the Registration Statement and the Prospectus, the Company’s certificate of incorporation and bylaws, each as currently in effect, the Agreement and such other records, documents, certificates, memoranda and other instruments as in our judgment are necessary or appropriate to enable us to render the opinion expressed below. We have assumed the genuineness of all signatures; the authenticity of all documents submitted to us as originals; the conformity to originals of all documents submitted to us as copies; the accuracy, completeness and authenticity of certificates of public officials; and the due authorization, execution and delivery of all documents by all persons other than the Company where authorization, execution and delivery are prerequisites to the effectiveness thereof. As to certain factual matters, we have relied upon a certificate of an officer of the Company and have not independently verified such matters.

We have assumed (i) that each sale of Shares will be duly authorized by the Board of Directors of the Company, a duly authorized committee thereof or a person or body pursuant to an authorization granted in accordance with Section 152 of the General Corporation Law of the State of Delaware (the “DGCL”), (ii) that no more than 10,000,000 Shares will be sold pursuant to the Agreement and (iii) that the price at which the Shares are sold will equal or exceed the par value of the Common Stock. We express no opinion to the extent that future issuances of securities of the Company, anti-dilution adjustments to outstanding securities of the Company or other matters cause the number of shares of Common Stock issuable under the Agreement to exceed the number of shares of Common Stock available for issuance by the Company.

Our opinion herein is expressed solely with respect to the DGCL. We express no opinion to the extent that any other laws are applicable to the subject matter hereof and express no opinion and provide no assurance as to compliance with any federal or state securities law, rule or regulation.

On the basis of the foregoing, and in reliance thereon, and subject to the qualifications herein stated, we are of the opinion that the Shares, when issued against payment therefor in accordance with the Agreement, the Registration Statement and the Prospectus, will be validly issued, fully paid and nonassessable.

COOLEY LLP 110 NORTH WACKER, SUITE 4200, CHICAGO, ILLINOIS 60606

T: (312) 881-6500 F: (312) 881-6598 COOLEY.COM

Our opinion is limited to the matters expressly set forth in this letter, and no opinion should be implied, or may be inferred, beyond the matters expressly stated. This opinion speaks only as to law and facts in effect or existing as of the date hereof, and we undertake no obligation or responsibility to update or supplement this letter to reflect any facts or circumstances that may hereafter come to our attention or any changes in law that may hereafter occur.

We consent to the reference to our firm under the caption “Legal Matters” in the Prospectus and to the filing of this opinion as an exhibit to the Company’s Current Report on Form 8-K to be filed with the Commission for incorporation by reference into the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission thereunder.

Sincerely,

COOLEY LLP
By:	/s/ Courtney M.W. Tygesson
	Courtney M.W. Tygesson

COOLEY LLP 110 NORTH WACKER, SUITE 4200, CHICAGO, ILLINOIS 60606

T: (312) 881-6500 F: (312) 881-6598 COOLEY.COM

XML

Document and Entity Information	Nov. 24, 2023
Cover [Abstract]
Amendment Flag	false
Entity Central Index Key	0001708493
Document Type	8-K
Document Period End Date	Nov. 24, 2023
Entity Registrant Name	Harpoon Therapeutics, Inc.
Entity Incorporation State Country Code	DE
Entity File Number	001-38800
Entity Tax Identification Number	47-3458693
Entity Address, Address Line One	611 Gateway Boulevard
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	(650)
Local Phone Number	443-7400
Written Communications	false
Soliciting Material	false
Pre Commencement Tender Offer	false
Pre Commencement Issuer Tender Offer	false
Security 12b Title	Common stock, par value $0.0001 per share
Trading Symbol	HARP
Security Exchange Name	NASDAQ
Entity Emerging Growth Company	true
Entity Ex Transition Period	false