NEW YORK (AP) — Controversial music producer Dr. Luke was once pop music’s top hitmaker, crafting hits for virtually every female pop star, from Katy Perry to Kelly Clarkson to Britney Spears. He’s returned to the charts in 2020, working on songs for rising and established rap stars, including Lil Wayne, Juice WRLD, Saweetie and Doja Cat.

The songmaster, who has been entangled in a bitter lawsuit with former collaborator Kesha since 2014, has produced and co-written Saweetie’s new single “Tap In,” the follow-up to her double-platinum smash “My Type.” Dr. Luke also co-wrote and co-produced Juice WRLD’s “Wishing Well,” taken from the rapper’s first posthumous album “Legends Never Die,” released last week.

The recent successes mean all three major U.S. record label companies have worked with Dr. Luke this year, even if he hasn’t always put his widely recognizable professional name to the new collaborations.

Dr. Luke marked a major comeback this year with the success of the Billboard Hot 100 No. 1 hit “Say So” by rapper-singer Doja Cat, who is signed to Dr. Luke’s Kemosabe Records. Dr. Luke, born Lukasz Sebastian Gottwald, produced several songs on Cat’s sophomore album “Hot Pink,” including single “Like That,” which is No. 5 on Billboard’s Hot R&B songs chart. He is the only producer with two songs in the Top 10 on the latter chart (“Say So” sits at No. 2).

For his work with Cat, he used the alias Tyson Trax. He used the same pseudonym for his production credit on Toronto rapper-singer Benny Mayne’s “Hokey Pokey,” released this year. For Lil Wayne’s “Shimmy,” a track featuring Cat on the deluxe edition of his latest album “Funeral,” Dr. Luke used the name Loctor Duke.

Label representatives for Saweetie, Juice WRLD, Lil Wayne and Cat didn’t immediately reply to emails seeking comment. Neither did a representative for Dr. Luke.

Luke has sprinkled his comeback among the major labels. Cat is signed to Sony Music’s RCA Records, while Saweetie is part of the Warner Music family. Lil Wayne releases music through his Young Money imprint and Republic Records, a division of Universal Music Group.

Before Dr. Luke topped the charts this year with “Say So,” he last had a No. 1 with Katy Perry’s “Dark Horse” in 2014. Months later, Kesha accused him of sexual assault during their yearslong partnership (Dr. Luke has vigorously denied the allegations.)

A New York court dismissed Kesha’s sexual abuse-related claims in 2016 because of legal issues, without ruling on whether the allegations were true. Kesha lost another round in February, when a New York judge said she made a defamatory statement about Dr. Luke on a different occasion: a 2016 text message telling Lady Gaga the producer had also raped Perry. Both he and Perry have denied it, and the judge said there was “no evidence whatsoever” to support the claim.

Kesha’s lawyers have said they plan to appeal the ruling, but it didn’t resolve other aspects of his defamation and breach-of-contract suit, including the crucial question of whether Kesha’s allegation that he raped her is true. The judge said that’s for a jury to decide at trial.

Outside of rap in 2020, Dr. Luke has produced music for pop singer Kim Petras, using the pseudonym MADE IN CHINA.