Barclays Plc and Deutsche Bank AG are due to appear before the Senate’s Permanent Subcommittee on Investigations next week to answer questions related to their sale of products to a hedge-fund manager that enabled the manager to skirt borrowing limits and avoid taxes, people with knowledge of the matter told Bloomberg.

The companies that are due to appear at the July 22 hearing – although a formal announcement has not been made – are Barclays, Deutsche Bank and Renaissance Technologies, a hedge-fund manager based in East Setauket, N.Y., and founded by billionaire James Simons. Renaissance manages around $25 billion, including its Medallion fund–run mostly for its own employees–which has one of the best investing records in history, with a return of more than 35 percent annualized over 20 years, according to Bloomberg.