Brafman and Spiro denied the allegations.
According to the lawsuit, Melissa Thompson met with Weinstein at his Manhattan office, where she turned on her computer's video recording capability to help demonstrate internet technology she wanted his company to buy.
Harvey Weinstein, center, listens during a court proceeding in NY during his arraignment on rape and other charges on May 25.
Caitlin Dulany, a second plaintiff, was sexually assaulted, battered, threatened and falsely imprisoned in Weinstein's hotel suite during the Cannes Film Festival in 1996, the lawsuit said.
Thompson went to a follow-up meeting with Weinstein at a restaurant at the Tribeca Grand Hotel that same day, and the meeting quickly moved to a hotel room, the suit says.
The third plaintiff, actress Larissa Gomes, alleges that Weinstein cornered her in a hotel room in Toronto in 2000, tried to get her to give him a massage and asked to see her breast.
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In this courtroom sketch, Harvey Weinstein, center, is escorted into New York County Criminal Court in New York on Friday, May 25, 2018.
Disgraced film producer Harvey Weinstein has been indicted on first- and third-degree rape charges, as well as one criminal sex act charge, involving two NY women.
Almost 100 women have now accused Weinstein of crimes ranging from sexual harassment to assault and rape going back decades.
"Deceptive tactics were used to entice her to turn over her visual and audio evidence of Weinstein's conduct (which she did)", it said. The complaint alleges Thompson spoke on the phone, exchanged texts and sent emails to Spiro, who she believed was working on Brafman's behalf. She recoiled and Weinstein became angry. Brafman, who represents Weinstein in his criminal case, said in a statement Friday that his firm has never represented Thompson and he has never met her or the other women identified in the new lawsuit.
Thompson said she was referred to Ben Brafman's law firm amid allegations from dozens of women that surfaced in the fall, according to a release obtained by The Associated Press. "In addition, while at this firm, he never met with Mr Weinstein nor did he have any responsibility whatsoever in connection with our representation of Mr Weinstein in any matter".