The assets of the Dolfinger-McMahon Foundation were provided by Henry Dolfinger, who died in June 1939, and in part from his son-in-law, J. Edward McMahon, who died in July 1951. The source of a majority of those assets was the Dolfinger Dairy, which was sold by Henry Dolfinger to Abbotts Dairies. The creators of the Foundation and donors of the funds now comprising the Foundation were Mrs. J. Edward McMahon (Caroline D. McMahon), the only child of Henry Dolfinger, and Mary M. McMahon, the only child of Mrs. J. Edward McMahon.

Both Caroline D. and Mary M. McMahon became quite enthusiastic about establishing a perpetual foundation to benefit charitable purposes and memorialize to some extent the Dolfinger and McMahon names.