Sen. Elizabeth Warren (D-Mass.) is challenging a top seller of private flood insurance to explain how it hopes to achieve a rapid takeover of the U.S. market now dominated by the federal government.

Warren sent a letter Tuesday to Neptune Insurance Holdings, a fast-growing technology company that sells flood insurance policies on behalf of insurance companies. At an October 2025 event at the White House, Neptune officials said the private sector can absorb 95 percent of flood insurance policies sold today by the National Flood Insurance Program, according to The New York Times.

Warren, the top Democrat on the Senate Banking Committee, pressed Neptune to show that it could replace the government’s National Flood Insurance Program, which has 4.6 million policies and is the nation’s primary flood insurer.

“Given the way Neptune appears to be positioning itself — echoing Project 2025’s call for an end to NFIP — Congress needs to understand the company’s role in the market and examine its claims to provide affordable and reliable insurance,” Warren wrote, referring to the conservative policy blueprint that proposes to shrink NFIP until the market is fully private.