The actress filed the complaint with California’s Department of Fair Employment and Housing (DFEH), claiming she was forced out of the show for "her refusal to remain silent in the face of a toxic culture at ('America's Got Talent') that included racist jokes, racist performances, sexual orientation discrimination, and excessive focus on female judges’ appearances, including race-related comments."
Union left the long-running talent competition show in November after only one season as a judge.
The complaint names Universal Television, LLC, Fremantle Productions, Simon Cowell and Cowell's company, Syco Entertainment as respondents.
NBCUniversal, the parent company of Universal Television and NBC, issued a statement responding to the complaint on Thursday, saying, "The allegation that anyone involved in this process threatened Ms. Union is categorically untrue."
"We took Ms. Union‘s concerns seriously, and engaged an outside investigator who found an overarching culture of diversity on the show," the statement said. "NBCUniversal remains committed to creating an inclusive and supportive working environment where people of all backgrounds are treated with respect."
NBCUniversal is also the parent company of NBC News.
The allegations in the complaint include:
Simon Cowell refusing to smoke outside despite requests from Union.
An act on the show performing in "blackface hands" despite concerns raised by both Union and Cowell.
Racist comments on the set.
A producer saying Union's hair was "too wild" and needed to be "toned down."
Though Union reported these alleged incidents to various NBC executives and "America's Got Talent" producers, the companies failed to follow up, leading Union to feel as though she "was the only one policing the show against racism," the complaint says.
NBC and the Screen Actors Guild launched separate investigations into Union's claims last year, and in December the actress said she had a "productive" meeting with NBC executives where she discussed her experience on the show.
NBC, Fremantle and Syco Entertainment released a joint statement on May 27 — responding to the allegations after they were featured in an interview Union gave to Variety — saying that their investigation "demonstrated an overall culture of diversity," but "also highlighted some areas in which reporting processes could be improved."
The complaint, however, states that Paul Telegdy, the chairman of NBCUniversal, attempted to "undermine the investigation" by "pressuring Union from providing her true experience of racial discrimination."
Telegdy, Union and Cowell did not respond to NBC News requests for comment.
“There are so many people who are committed to making NBCUniversal and Comcast different, who truly want to be a part of the solution and on the right side of history,” Union told Variety in the interview published May 27. “In the same breath, there are some people who want the wheels of change to come to a grinding halt because they feel that their privilege is being challenged.”
DFEH complaints are often precursors to lawsuits. The complaint alleges that Union is entitled to recover damages as a result of acts that were committed "with the wrongful intention of injuring Union" and "in conscious disregard" of her rights.