Writer E. Jean Carroll has sued Donald Trump in the US state of New York for defamation and battery in relation to her claim he raped her in the 1990s.
Ms Carroll is among the first to sue under the Adult Survivors Act, which came into effect on Thursday.
The state law allows a one-year period for victims to file sexual assault lawsuits in New York over claims that would have otherwise exceeded the statute limitations.
Ms Carroll alleges the attack took place in a New York luxury department store dressing room 27 years ago.
The former president has denied the allegations against him.
Ms Carroll previously sued Trump for defamation over statements he made in 2019 when he denied her claim that he raped her in the 1990s.
Her new lawsuit alleges a second claim of defamation over statements Trump made last month.
It also alleges battery as she seeks to hold him accountable for the supposed sexual assault.
The Adult Survivors Act allows victims to come forward if the sexual assault occurred when they were over the age of 18 and took place on a date that exceeds time limits that exist on most felonies.