The estate of late billionaire Robert Brockman has agreed to pay roughly $750 million in back taxes and penalties, resolving a long-running tax dispute with the Internal Revenue Service, according to a filing made Tuesday in U.S. Tax Court.

Brockman, the former chief executive of Reynolds and Reynolds, died in 2022 while awaiting trial in what prosecutors described as the largest criminal tax fraud case ever brought against an individual in the United States. He had been accused of using offshore entities to conceal approximately $2 billion from the IRS.

Following Brockman’s death, the dispute over his alleged unpaid tax liabilities shifted to Tax Court. Under the agreement outlined in Tuesday’s filing, the estate will pay about $456 million in back taxes and $294 million in penalties.

Counsel for the parties did not immediately respond to requests for comment Tuesday.

Federal prosecutors charged Brockman in 2020, alleging that for more than two decades he hid assets from the IRS and concealed his control over offshore companies and trusts by filing false tax returns and failing to submit required foreign bank and financial account disclosures. At the time, the government said the case was the largest criminal tax fraud prosecution ever pursued against an individual.

In 2022, attorneys for Brockman and the federal government clashed over his health and whether he was fit to stand trial. Brockman’s lawyers told a Texas federal court that he suffered from Parkinson’s disease and other conditions that caused cognitive decline, which they said was worsened by a recent bout with COVID-19.

A court ruling issued in May 2022 rejected those claims, finding evidence that Brockman exaggerated symptoms of cognitive impairment. The court said he was able to manage or meaningfully engage with his company’s operations while also failing certain cognitive tests, and concluded that he was competent to stand trial.

The IRS is represented by Lewis A. Booth II. Brockman’s estate is represented by Frank J. Jackson of McDermott Will and Schulte.

The case is Estate of Robert T. Brockman, Deceased et al. v. Commissioner of Internal Revenue, Case No. 764-22, in the U.S. Tax Court.