Exhibit C

Joint Filing Statement

I, the undersigned, hereby express my agreement that the attached Schedule 13D (and any amendments thereto) relating to the beneficial ownership by the undersigned of the equity securities of Harpoon Therapeutics, Inc. is filed on behalf of each of the undersigned.

Date: February 11, 2021

MPM BIOVENTURES 2014, L.P.
By:	MPM BioVentures 2014 GP LLC,
	its General Partner
By:	MPM BioVentures 2014 LLC,
	Its Managing Member
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Managing Director
MPM BIOVENTURES 2014 (B), L.P.
By:	MPM BioVentures 2014 GP LLC,
	its General Partner
By:	MPM BioVentures 2014 LLC,
	Its Managing Member
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Managing Director
MPM ASSET MANAGEMENT INVESTORS BV 2014 LLC
By:	MPM BioVentures 2014 LLC
	Its: Manager
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Managing Director
MPM ASSET MANAGEMENT LLC
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Member

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MPM BIOVENTURES 2014 GP, LLC
By:	MPM BioVentures 2014 LLC,
	Its Managing Member
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Managing Director
MPM BIOVENTURES 2014 LLC
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Managing Director
UBS ONCOLOGY IMPACT FUND, L.P.
By:	Oncology Impact Fund (Cayman) Management L.P.,
	its General Partner
By:	MPM Oncology Impact Management LP,
	Its General Partner
By:	MPM Oncology Impact Management GP LLC
	Its General Partner
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Managing Director
ONCOLOGY IMPACT FUND (CAYMAN) MANAGEMENT L.P.
By:	MPM Oncology Impact Management LP,
	Its General Partner
By:	MPM Oncology Impact Management GP LLC
	Its General Partner
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Managing Director
MPM ONCOLOGY IMPACT MANAGEMENT LP
By:	MPM Oncology Impact Management GP LLC
	Its General Partner
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Managing Director

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MPM ONCOLOGY IMPACT MANAGEMENT GP LLC
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke
Title:	Managing Director
By:	/s/ Todd Foley
Name:	Todd Foley
By:	/s/ Luke Evnin
Name:	Luke Evnin
By:	/s/ Ansbert Gadicke
Name:	Ansbert Gadicke

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