The American Civil Liberties Union (ACLU) Foundation is the charitable-organization arm of the American Civil Liberties Union, a left-leaning activist organization.
The ACLU Foundation is an affiliate organization of the ACLU and mainly engages in the organization’s litigation and communication efforts while the ACLU proper, a 501(c)(4) lobbying organization, leads the organization’s lobbying and legislative work at the federal and state levels. 
ACLU Foundation affiliates often argue social-liberal advocacy cases and bring civil rights lawsuits within their respective states. In one illustrative example, the ACLU Foundation helped represent Aimee Stephens in a lawsuit against her former employer, R.G. & G.R. Harris Funeral Homes, for firing Stephens after announcing that she was transgender and would present herself as a female at work. After Stephens’s death in May 2020, Stephens’s estate continued the case, resulting in a settlement of $130,000 to Stephens’s estate and $120,000 to the ACLU Foundation for court and attorney’s fees. 
The organization’s tax returns for 2018 reported over $205 million in total revenue, over $59 million more in revenue than the previous year. 
The ACLU Foundation frequently provides grants to state-level affiliate organizations. According to 2018 tax returns, the ACLU Foundation provided the ACLU Foundation of Texas with a $315,000 grant and also provided a $375,000 grant to the ACLU Foundation of Mississippi, among other grants. 
The ACLU Foundation receives contributions from several corporate supporters. In 2020, after Black Lives Matter-inspired protests across the country, a number of corporate entities pledged to support organizations that promote civil liberties, including the ACLU Foundation. Amazon announced a $10 million donation spread amongst a number of left leaning organizations such as the ACLU Foundation, Black Lives Matter, and the NAACP. 
In 2020, Conagra Brands Foundation announced that it was partnering with the ACLU Foundation, as well as United Way, for a national employee fundraising campaign called “United For Change” with the goal of alleviating poverty and advancing civil liberties. 
In addition to corporate pledges, the ACLU Foundation also accepts individual donations. Notably, former hedge fund manager David Gelbaum gave more than $90 million to the ACLU Foundation between 2005 and 2009.  Gelbaum, who co-founded Wellspring Philanthropic Fund, a left-of-center dark money organization, has also gifted more than $100 million to the Sierra Club, an environmental activist group. 
The ACLU and the ACLU Foundation share essential staff and executive leadership members. Anthony Romero has worked as the executive director of the ACLU and ACLU Foundation since 2001 and is the first Latino and openly gay man to serve in that capacity. 
Susan Herman has served as the president of the ACLU since 2008 and is also the president of the ACLU Foundation Board of Directors.  Robert Remar, an attorney at Rogers & Hardin LLP, is the vice president and treasurer of the board.