Exhibit 99.6
Joint Filing Agreement
In accordance with Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a statement on Schedule 13D (including amendments thereto) with respect to the common stock, par value $0.0001 per share, of Harpoon Therapeutics, Inc., a Delaware corporation, and further agree that this Joint Filing Agreement be included as an Exhibit to such joint filings. In evidence thereof, the undersigned, being duly authorized, have executed this Joint Filing Agreement as of the date set forth below.
| Date: January 17, 2024 | MERCK & CO. INC. | |||||
/s/ Robert M. Davis | ||||||
| Name: | Robert M. Davis | |||||
| Title: | Chairman and Chief Executive Officer | |||||
| MERCK SHARP & DOHME LLC | ||||||
/s/ Sunil A. Patel | ||||||
| Name: | Sunil A. Patel | |||||
| Title: | SVP, Business Development & Licensing | |||||
| HAWAII MERGER SUB, INC. | ||||||
/s/ Dalton Smart | ||||||
| Name: | Dalton Smart | |||||
| Title: | Senior Vice President, Global Controller | |||||
