In late July, Senate Finance Committee Chair Ron Wyden and House Ways & Means Committee Chair Richard E. Neal released new data about the increased use of “mega-IRAs” over the last decade. According to the report, the number of Americans with at least $5 million in an IRA has more than tripled over the last eight years.

Traditional and Roth IRAs have limits on the amount an individual can contribute each year. However, hard-to-value assets, such as the stock of a start-up company, can be contributed to an IRA, where the assets can significantly appreciate in value.

Senator Wyden has not outlined the specific measures he would take to limit the “mega-IRAs,” but indicated that he plans to introduce language to existing bipartisan retirement bills.