Lady Gaga sued for $35m by ex-boyfriend

Lady Gaga is being sued for $35m by Rob Fusari, her former boyfriend and manager. He claims he discovered the multi-platinum selling singer and helped develop her act – coming up with her stage name and co-writing many songs – only for her to renege on their business deal when he ended their romantic relationship.

Fusari alleges he is entitled to a 20 per cent share of Gaga's song royalties, 15 per cent of merchandising and other payments - but has only received $611,000. The imputation of the lawsuit, which begins with the aphoristic observation, "All business is personal", is that Gaga is a 'woman scorned' who is enacting her revenge financially.

Fusari first met Stefani Joanne Angelina Germanotta when he was already an established producer and writer – having co-written Bootylicious for Destiny's Child and Wild, Wild West for Will Smith. He was looking for a "dynamic female rock-n-roller" to front a new group when a friend suggested Germanotta, who took a Port Authority bus out to his New Jersey studio to meet him in 2006.

The lawsuit contains tantalising glimpses of this pre-Gaga Germanotta for fans. Fusari says he was so taken aback when he saw "the young Italian girl 'guidette' that arrived at [his] doorstep" that he feared he had made a "mistake" in even meeting her. But when he heard her play one of her songs on his piano he knew "within seconds" she had "star potential". "The trick would be coaxing it out of her," he writes.

According to the lawsuit, the two then worked together seven days a week "radically reshaping her approach" while Fusari persuaded Germanotta to drop rock riffs for electro beats. It was at this stage that they co-wrote two of her later hits, Beautiful, Dirty, Rich and Paparazzi.

As for the famous stage name, Fusari says he was in the habit of playing Queen's Radio Gaga whenever Germanotta arrived at his studio, and had started calling her that. Sending her a message from his mobile phone one day, the "autocorrect" changed 'Radio' to 'Lady'. She loved the new title, and it stuck. A spellchecker would not challenge 'radio', which is a valid English word – and there's no way predictive text could change it to 'lady' - but other than that, it's a good story.

The pair's relationship soon reached "a new, personal and romantic level" and they began to spend all their time together as a couple, the lawsuit claims. They formed a company in conjunction with her father "for the purpose of exclusively professionally exploiting Germanotta and the songs" which helped Gaga to her first record deal. Then, in January 2007, Fusari says he took the decision to end the romance which had degenerated into "constant bickering".

The producer alleges that since ending the romantic relationship with Lady Gaga, he has been cut out of her professional life – and has not received his due. Gaga has not made any comment on the lawsuit as yet, but recent reports say she has kept an unusually low profile in Australia, where she is currently touring - even using a double to distract the paparazzi. ·