Thomas B. Sheridan and his wife, Elizabeth, founded The Sheridan Foundation in 1962. Mr. Sheridan was born in 1886 to Irish immigrant parents of modest means. Mr. Sheridan learned the value of education, and it was on this principle that the Foundation was formed. He was the founder of the American Bank Stationery Company in Baltimore in 1927, which grew to become one of the largest check printing companies in America, with locations across the United States.

The Foundation was initially led by Thomas M. Sheridan, the grandson of Thomas B. and
Elizabeth M. Sheridan. Under his presidency, the Foundation made diverse grants, including to educational institutions, inside and outside the State of Maryland. Upon Mr. Sheridan’s death in 1974, James L. Sinclair became President.  Mr. Sinclair had been a Trustee since 1971, had been a President of American Bank Stationery Company, and was married to Elizabeth Sheridan Sinclair, a
granddaughter of the Foundation’s founders. In 1974, Mrs. Sinclair became a Trustee and Vice-President/Executive Director of the Foundation until her passing in 1987. It was under their direction and that of late Trustee L. Patrick Deering that the Foundation refocused its efforts to its current mission.

Upon the death of James L. Sinclair in 2010, the Trustees elected his son, John B. Sinclair, a trustee since 1979, as President of The Sheridan Foundation and he remained in this position through 2023, after which he became Vice President. His daughter, Jessica Sinclair Schram, a Trustee since 2010, became President in 2024.