An unrestricted free agent this summer, Young faces no criminal charges.
The lawsuit, filed in Los Angeles Superior Court, contends that Young, who at the time played for the Washington Wizards, gave the woman gamma hydroxybutyrate, commonly known as GHB or the date-rape drug, and later had nonconsensual sex with her.
The suit contends that Young met the woman and a friend for a drink at West Hollywood's Crown Bar on Aug. 12, 2011. Young approached them with drinks.
Young met the woman who made the allegations on two previous occasions. The next morning, the plaintiff contends, she woke up naked and in bed with Young in his apartment.
When she asked Young why she was naked and in his bed, according to the complaint, Young said they had started having sex but stopped when she passed out. When she asked Young to take her home, he complied.
Ensuing tests later confirmed that the woman had been given GHB, according to the suit, which also says that she underwent exams at the UCLA Santa Monica Rape Treatment Center, which revealed anal and rectal bleeding.
The suit says that the woman has undergone psychiatric evaluations and treatment.
In 59 games with the Sixers this season, including 17 starts, Young averaged 10.6 points and 2.2 rebounds.
Contact John N. Mitchell at firstname.lastname@example.org. Follow on Twitter @JmitchInquirer.