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DALLAS (CBSDFW.COM/AP) — The IRS wants $3.2 billion to cover back taxes that it says are owed by a prominent Texas businessman and his late brother who the IRS says hid income by setting up overseas trust funds.

The Internal Revenue Service detailed its claim in documents filed Wednesday in U.S. Bankruptcy Court in Dallas. It seeks to recover more than $2 billion in unpaid income taxes, interest and penalties from Sam Wyly and more than $1.2 billion from the estate of his brother, Charles Wyly.

The late Charles Wyly, who died in a 2011 car wreck in Aspen, Colorado, was the billionaire who donated $20 million to build the landmark theater bearing his and his wife’s namesake in the AT&T Performing Arts Center in Dallas.

Stewart Thomas, a lawyer for the Wylys, called the IRS claims “unfair and absurd.”

“The IRS has known about these transactions for over 20 years, but they never informed the Wylys that they owe a penny of additional tax,” Thomas said.

Sam Wyly filed for bankruptcy in October, five months after a civil jury in New York found the brothers had engaged in a 13-year fraud that involved creating a web of offshore trusts and subsidiaries to hide stock sales.

A federal judge in February approved Securities and Exchange Commission fines of $198 million against Sam Wyly and $101 million against the estate of his brother, who died in a car crash in 2011.

At the time of the bankruptcy Sam Wyly listed assets of $100 million to $500 million, but his lawyers said he needed to file for bankruptcy protection “due to the massive costs of investigations and then litigation” by the SEC and the collection of the court judgment.

The Wylys built, grew and sold several companies including Sterling Software, which they sold for $4 billion just before the dot-com bubble burst in 2000, and Michaels Stores, which was sold in 2006 for $6 billion.

The SEC sued the Wylys in 2010, alleging the brothers used proceeds from secret sales of stock in their companies to buy ranches and condominiums around Aspen, Colorado; a horse farm near Dallas; art and jewelry. The jury decision last year was a big victory for the SEC after it lost a high-profile civil case against businessman and Dallas Mavericks owner Mark Cuban.

The Wyly brothers were also major donors to Republican candidates and causes.

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