Wall Street Journal:  IRS Pays $38 Million in Whistleblower Case, by Laura Saunders:

The IRS has awarded an anonymous whistleblower $38 million for information leading to the recovery of between $127 million and $254 million in corporate taxes, according to the whistleblower's attorney.

The payment is believed to be the second-largest whistleblower award under a program created by Congress that took effect in 2007. The program awards between 15% and 30% of the taxes recovered by the IRS. In August, whistleblower Bradley Birkenfeld received an award of $104 million in connection with information he provided the IRS concerning offshore tax evasion promoted by Swiss banking giant UBS.

The whistleblower's attorney, Scott Knott of Ferraro Law Firm in Washington, declined to name the whistleblower or the firm involved, although he said the corporation is among the top 500 public firms in the country. He released a redacted copy of the IRS's award notice verifying that the whistleblower received $38,037,899.