The Hilda Mullen Foundation is a grantmaking trust created by investment manager Martin Whitman and his wife Lois Whitman.
The foundation is a left-of-center organization which contributes to universities, pro-LGBT, pro-government-controlled healthcare, pro-abortion, liberal activism, and anti-capital punishment organizations. The Hilda Mullen Foundation also provides grants and contributions to lobbies which push the United States government towards supporting and promoting left-leaning policies within Israel.
The Hilda Mullen Foundation was created by Martin and Lois Whitman in 1999 as a non-profit grant-making organization and trust. 
Martin Whitman (1924 – 2018) was the co-founder and co-chief investment officer of Third Avenue Management, a highly successful investment company. The resources to create Third Avenue Management were the result of a highly publicized risk Whitman took in 1974 by purchasing $100,000 of mortgage bonds in the then bankrupt Penn Central Railroad Company.  In 2012, Whitman stepped down as manager of Third Avenue Fund, an organization with a net value of $3.4 billion in investor assets. 
While generally in favor of capitalism over command based economies, Whitman was a lifelong critic of free-market theories advocated by economists such as Milton Friedman and Friedrich Hayek. Whitman was a strong advocate for highly regulated markets, highlighting Japan, China, Sweden, and Singapore as countries with better economic structures than the United States.  Whitman believed in extensive government regulation and intervention in the economy, believing that optimally efficient economic transactions were not possible without such intervention, stating that “government has a necessary role in determining how control persons are incentivized; and where the private sector will allocate resources in accordance with the invisible hand so that private control persons can maximize wealth for themselves, and also, by indirection, their constituents who are usually the owners of private enterprises.” 
In 2017, the Hilda Mullen Foundation received $2,811,375 in grants and $70,928 in profit and dividends from securities. 
The Hilda Mullen Foundation possessed $2,592,751 in savings and temporary cash investments in 2017 and disclosed a total of $11,453,080 in assets. 
In 2016, the Hilda Mullen Foundation contributed to many left-of-center organizations and universities including a $200,000 grant to the American Civil Liberties Union, and grants in varying amounts to The New School, University of Pennsylvania Board of Trustees, and the Columbia University School of Arts. 
In 2017, the Hilda Mullen Foundation issued a total of $600,750 in contributions, gifts, and grants to left-of-center organizations.
Organizations which received contributions or grants from the Hilda Mullen Foundation in 2017 include the abortion rights groups Center for Reproductive Rights and National Partnership for Women and Families, the liberal Israel-policy group Israel Policy Forum, the liberal activist group Mississippi Center for Justice, the LGBT-interest groups InterAct and Outright Interaction International, and the anti-capital-punishment group Equal Justice Initiative.