Methods and compositions are provided for recombinant DNA production of Factor VIIIC and truncated derivatives thereof. Based on amino acid sequences, probes are developed for isolating messenger RNA, cDNA and/or chromosomal DNA encoding for Factor VIIIC. The Factor VIIIC gene in its entirety, a fragment thereof, or a cDNA is then used for expression of Factor VIIIC in a host.The bacteriophage .lamda.FVIII23D containing the 14.43 kb EcoRI fragment was deposited at the A.T.C.C. on Jan. 4, 1984 and given Accession No. 40094. Also, the vector pSVF8-200 was deposited at the A.T.C.C. on Jul. 17, 1985 and given Accession No. 40190.