donald sterling
Donald Sterling is prepared to fight to keep the Los Angeles Clippers. Reuters

Donald Sterling, the now-banned co-owner of the Los Angeles Clippers basketball team, has hired four private firms to investigate the NBA’s former and current commissioners, and its 29 other owners, a person close to Sterling's team of lawyers told Associated Press, or AP.

The source, who was not authorized to speak publicly, told AP late Thursday that the investigators have been offered a six-figure budget to scrutinize the league’s finances, compensations paid to the present and former commissioners, and previous unfair conducts, within 30 days. Sterling’s primary targets reportedly include previous NBA Commissioner David Stern and current Commissioner Adam Silver.

"The gloves are off, as they say," the source told AP. "Have them dig up all the dirt they can find."

The NBA banned Sterling for life on April 29 and fined the businessman $2.5 million after a tape surfaced in which Sterling was found to have made racist comments.

According to the source, investigators have also been asked to find out if any other NBA team owner has ever made racist or sexual remarks. The source also reportedly said that Sterling agreed to hire the investigators after recent legal proceedings in probate court, which deals with matters related to the administration of estates.

"He realized these guys will literally go to any low to get this sold," the source told AP. "Even if it gets (him) nothing other than exposing all these guys and shaking up the league and seeing a change in the leadership of the league, it'll be worth it to him."

The 80-year-old former attorney is also reportedly suing the NBA for $1 billion in federal court alleging that the league violated his rights by believing information based on an “illegal” recording. The lawsuit also reportedly claims that the NBA has committed a breach of contract by fining Sterling and forcing him to sell his team.

"Now his objective is to demonstrate for everybody that the NBA is a damned hypocrite," Bobby Samini, Sterling’s attorney, told ESPN, on Wednesday. "We're going to pull every case against the NBA. Then we'll demonstrate that the culture of racism and gender discrimination is born at the NBA, where Adam Silver has worked in a high-level position for a long time."

Meanwhile, Sterling’s attorneys will also face wife Shelly Sterling’s attorneys in probate court on whether she has the sole right to negotiate a $2 billion deal to sell the LA Clippers to Steve Ballmer, former CEO of Microsoft. The four-day hearing is reportedly scheduled to take place sometime in July.

Shelly’s attorney Pierce O'Donnell reportedly claimed that she made the negotiation after experts determined that Sterling does not meet the standard rule of The Sterling Family Trust, which owns the LA Clippers with Sterling and Shelly each owning a 50 percent share. Based on a provision related to the mental capacity of the trustees, the trust is reportedly relying on expert opinion that Sterling is mentally unfit and has made Shelly the sole decision maker.