WE’VE always assumed the biggest problem anyone would have with Lady Gaga would be sitting behind her when she wears yet another of her infamously ridiculous headpieces (or when she forgets to put on pants yet again).

However, we’re told her bitter ex-boyfriend and producer Rob Fusari is less than thrilled because he claims the “Telephone” singer ditched him when she became big and didn’t give him his fair share of the royalties.

Now, according to Yahoo! News, he’s hoping to score a cool US$30.5 million in supposed back pay by taking her to court. Fusari co-wrote some of her hits like “Paparazzi” and “Beautiful, Dirty, Rich,” and claims he had 20 per cent share in their joint venture Team Love Child LLC. But, by the time Gaga signed with Interscope Records and shot to the top of the charts, their relationship had ended and Fusari said he never got his cut of her earnings.

He has producing credits in her 2008 album The Fame, which sold more than 3 million copies. The lawsuit states that he got cheques for over US$600,000 but claims that was not the total amount he is entitled to receive.

As of Sunday, the Grammy-winning pop star has filed a counter suit against the Jersey producer, claiming that Fusari lured her into signing a misleading contract entitling him to “unlawful compensation”. He is accused of acting as her talent agent without a license to represent musicians in that capacity.

Fusari, who helped pen and produce hits such as Destiny’s Child’s “Bootylicious” and “Wild Wild West” by Will Smith, sang a different tune during an interview in January. At the time, he declared that he only wanted a verbal “thank you” from the diva.

“There’s different ways to thank people. It doesn’t have to be in the media. It doesn’t have to be on record. I don’t think she has to take it out on a billboard…’Thank you’ would have been fine.”

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