Leon Black, former chairman of the Museum of Modern Art, was accused of defamation and sexual abuse in a lawsuit filed on Tuesday, June 1. The billionaire recently stepped down from his leadership role at MoMA following a review of his former ties with sex offender Jeffrey Epstein, but remains a member of the museum’s board. Amid public controversy, he also resigned from his roles as CEO and chairman of his private equity company, Apollo Global Management.

The plaintiff, Guzel Ganieva, says that Black defamed her by describing their former relationship as a “consensual affair” instead of what she previously described as “appalling forced sexual misconduct,” according to the lawsuit. The accuser also said that she was defamed by Black’s allegations that she had extorted money from him.

Ganieva, a former model, first detailed her allegations against Black in March when she tweeted that the billionaire had “sexually harassed and abused” her “for years.” In one of several tweets, she wrote:

It started in 2008 when I met with him to discuss work. While he understood my career aspirations, he could not understand me when I refused his sexual advances. I was bullied, manipulated, threatened, and coerced. Similarly, under duress, I was forced to sign an NDA in 2015.

In a statement to the New York Post in April, Black said that he “foolishly had a consensual affair with Ms. Ganieva that ended more than seven years ago.” He called the accuser’s allegations against him “completely fabricated” and claimed that he had “made substantial monetary payments to her, based on her threats to go public concerning our relationship, in an attempt to spare my family from public embarrassment.”

In recent years, Black has been the subject of multiple widely publicized controversies centering his associations with Jeffrey Epstein. In January, a company review revealed that Black had paid Epstein $158 million in tax and estate planning fees between 2012 and 2017. The report, however, cleared Black of any misconduct. In February, over 150 artists, including Nan Goldin, Hito Steyerl, Xaviera Simmons, Michael Rakowitz, and Guerilla Girls, called on MoMA to remove Black from its board and reimagine its donor policies. A Hyperallergic investigation spotlighted artists’ concerns about Black’s investments in defense contractors with ties to the murder of civilians in Iraq. As public scrutiny intensified, the billionaire announced in March that would not stand for re-election as MoMA’s chairman. In April, MoMA announced philanthropist and Donald Trump ally Marie-Josée Kravis as his successor. (MoMA has not responded to Hyperallergic’s request for comment regarding Ganieva’s lawsuit.)

In her lawsuit, Ganieva seeks unspecified damages for charges of defamation, intentional infliction of emotional distress, and gender-motivated violence. “The truth will reveal a violent, sadistic side to Black that he has shielded from public view for decades,” the lawsuit said.

In an email to Hyperallergic, a spokesperson for Black wrote that Ganieva’s allegations of harassment and other inappropriate behavior are “categorically untrue.” The spokesperson continued:

This frivolous lawsuit is riddled with lies, and is nothing more than a wholesale fiction.  The truth is that Leon Black had a wholly consensual relationship with Ms. Ganieva for six years, and then, as we have previously advised the criminal authorities, Mr. Black was subsequently extorted by Ms. Ganieva for many years and made substantial monetary payments to her based on her threats to go public about their relationship and cause him reputational risk and harm to his family.  Mr. Black emphatically denies each and every spurious allegation put forth in this lawsuit and looks forward to disproving them in court.

Ganieva’s attorney could not be reached for immediate comment.

Controversy continues to hound MoMA beyond Black’s entanglements. For the past eight weeks, a coalition of artist-activist groups has held weekly protests across from the museum, calling on its leadership to cut ties with problematic billionaires and seek an alternative, community-oriented model.

“Whether Black stays or goes, a consensus has emerged: beyond any one board member, MoMA itself is the problem,” the group named the International Imagination of Anti-National Anti-Imperialist Feelings (IIAAF) wrote in a statement in April. “The rot is at the core of the institution,” the activists added.