Producer Dr. Luke is seeking $50 million (GBP37.7 million) in damages from Kesha, insisting his career has suffered in the wake of her abuse allegations against him.
The Timber hitmaker has been locked in court proceedings with her former mentor since 2014, when she accused Luke of physical, sexual and emotional abuse throughout their years-long working relationship - allegations he has vehemently denied.
She lost her bid to be released from her contract with his Kemosabe Records label in 2016, but is pressing on with the legal fight, while trying to move forward with her career.
Dr. Luke is now claiming his livelihood has suffered immensely as a result of the ongoing legal proceedings and the producer is seeking $50 million in damages from Kesha.
According to The Blast, Dr. Luke, real name Lukas Gottwald, believes he would have racked up $29.9 million (GBP22.6 million) in "producer and publishing royalties", $8.7 million (GBP6.6 million) from "co-writing tracks with songwriters on his label", and $10.2 million (GBP7.7 million) for producing Katy Perry's fourth, fifth, and sixth albums over the next 10 years, if it wasn't for the legal wrangle hanging over him.
However, Kesha's lawyers have argued his math is based on past earnings, insisting he no longer works with the top A-list talent he once did.
There's more bad news for Kesha - judges at an appeals court have also reaffirmed a previous ruling that Kesha cannot be released from her contract with Gottwald and his label.
The Tik Tok singer's career stalled as a result of her legal clash with Dr. Luke, but she enjoyed critical acclaim with her 2017 album Rainbow and is out on tour with Macklemore this summer.