Christina Aguilera [ tickets ] has filed a lawsuit against her former manager Steven Kurtz and his Marquee Management firm, claiming that Kurtz and his firm took money from the singer to which it was not entitled, according to published reports.

Aguilera's agreement with Kurtz reportedly outlined an arrangement in which any assistance Kurtz received from other people in managing Aguilera would be rendered at no additional cost to the singer. The lawsuit contends that, despite that arrangement, Kurtz was paying an associate, Katrina Sirdofsky, $4,000 per week from Aguilera's coffers, in addition to Kurtz's 20 percent commission.

In the complaint, filed in Los Angeles Superior Court on Friday (10/13), Aguilera is suing Kurtz and Marquee Management for fraud, and is also suing both Kurtz and Sirdofsky individually for breach of fiduciary duty. The singer has parted ways with Marquee Management, and is now managed by Irving Azoff, whose artist roster includes Don Henley, the Eagles and Seal.

Aguilera is also accusing Kurtz of exercising "improper, undue, and inappropriate influence over [Aguilera's] professional activities," and of "inducing" Aguilera to sign a written agreement in 1999 that established him as her exclusive personal manager.

The singer has reportedly also filed a petition with the California State Labor Commission to have the contract made null and void.

Attorney Daniel M. Petrocelli is representing Aguilera in the matter. Petrocelli was lead council in the multi-million dollar wrongful-death suit Fred Goldman pursued against O.J. Simpson, according to Petrocelli's law-firm biography.

Kurtz, Azoff and Aguilera's lawyers could not be reached for comment.

Aguilera is currently on tour in support of her multi-platinum, self-titled, debut album, which has been certified by the Recording Industry Association of America for shipping over 7 million copies. The current leg of the singer's tour is scheduled to end in Hawaii this Saturday (10/21), according to her official website.

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