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Mike Tyson is seeking more than $5 million in damages from Live Nation for breach of fiduciary duty, among other charges.

LOS ANGELES -- Mike Tyson sued a financial services firm owned by Live Nation Entertainment on Wednesday, claiming one of its advisers embezzled more than $300,000 from the former heavyweight champ and cost him millions more in lost earnings.

The lawsuit claims that Live Nation and its company SFX Financial Advisory Management Enterprises haven't given the boxer and his wife, Lakiha, a full accounting of their losses. The company returned some of the embezzled money but wanted the Tysons to sign a nondisclosure agreement, which they refused, the suit states.

The lawsuit seeks more than $5 million in damages for breach of fiduciary duty, negligent hiring, unjust enrichment and other claims.

Messages left for a spokeswoman for Live Nation Entertainment Inc. and at the Washington, D.C., offices of SFX were not immediately returned.

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The embezzlement prevented the Tysons from emerging from bankruptcy, and forced them to hire new advisers and turn down lucrative contracts, the lawsuit claims. The case states the couple trusted Brian Ourand, their adviser at SFX, so much that he attended their wedding.

Ourand, who could not be reached for comment, has since left SFX, according to the lawsuit. The filings claim his conduct has not been reported to regulators.

"Defendants did not secure, protect, safeguard and appropriately apply the Tysons' finances for their intended purposes," the case states, "but instead misappropriated said funds for the benefit and enrichment of SFX/Live Nation.

The former boxer has broadened his career in recent years, including appearing in "The Hangover" and leading a one-man autobiographical show, "Undisputed Truth."