Cytokine-receptor like factor 3 (CRLF3) is a protein with an as yet unknown function. CRLF3 has been shown to interact with the members of the Hippo pathway in HEK cells but the function of this interaction was not elucidated. Crlf3 null mice are viable and health but present with an isolated reduced platelet count from birth, confirming CRLF3 has a role in platelet production. We performed affinity purification followed by liquid chromatography coupled to tandem mass spectrometry to identify CRLF3’s binding partners in human megakaryocytes.