Almost half of the artists currently featured in MoMA PS1’s exhibition “Theater of Operations: The Gulf Wars 1991–2011” have signed an open letter urging New York’s Museum of Modern Art (MoMA) and PS1 to divest from “any trustees and sources of funding that profit from the suffering of others.” The letter arrives a little over two months after British artist Phil Collins pulled his work from the show days before its opening, and specifically targets the museum’s relationship to Leon Black, the chairman of MoMA’s board of trustees and an ex-officio member of PS1’s board, for his links to the US-based private security firm Blackwater.

The security contractor, which rebranded as Constellis Holdings LLC before it was acquired by Black’s private equity firm Apollo Global Management in 2016, made international headlines in 2007 after former military personnel employed by the company fired on dozens of unarmed Iraqis in Nisour Square, Baghdad. The incident, which forced the US to consider its reliance on private contractors in conflict zones, unfolded in the middle of the Iraqi War, which officially ended in 2011. The armed conflict as well as the violence that followed in subsequent years have impacted many of the artists whose works are displayed in MoMA PS1’s exhibition. “We appreciate the visibility this exhibition gives to the Iraq wars and to the work of Iraqi artists; however, we also wish to make visible MoMA’s connection to funds generated from companies and corporations that directly profit from these wars,” the letter reads.

In addition to Black, activists have previously called out the business dealings of MoMA trustees Larry Fink, the CEO and chairman of the investment firm BlackRock, for his connections to private prisons, and Steven Tananbaum, the founder, managing partner, and chief investment officer of GoldenTree Asset Management, for his role in Puerto Rico’s debt crisis. While MoMA has a different board than PS1, some artists, including Michael Rakowitz, have called for the Queens outpost to divest from its parent institution. After Collins withdrew his work Baghdad screentests, 2002, from “Theater of Operations,” Rakowitz asked that the museum pause his video work RETURN in protest of the board members. The institution refused to comply with his request, which prompted the artist to pause the work himself on Saturday, January 11.

“We call on PS1 to stand by its stated mission and, together with MoMA, take a truly radical position by divesting from any trustees and sources of funding that profit from the suffering of others,” the letter reads. “MoMA has just rebuilt itself and opened a newly renovated and expanded museum with a more global and inclusive curatorial narrative; surely it must also be capable of rebuilding its board and envisioning new ethical standards and best practices when it comes to sourcing philanthropic support.” Signed by thirty-seven artists—including Rasheed Araeen, Ali Eyal, the Guerrilla Girls, Mona Hatoum, Hiwa K, Laura Poitras, Rakowitz, Martha Rosler, Mohammed Al Shammarey, and Nazar Yahya—the letter was submitted to the exhibition’s curators Ruba Katrib and Peter Eleey last week.