When you're the largest shareholder in Fannie Mae and Freddie Mac, you tend to have opinions about how they should be run. Bill Ackman has plenty of those, and he's ready to share his latest thinking.

The billionaire hedge fund manager plans to unveil a new proposal for the mortgage-finance giants during a livestream event on Tuesday, November 18. According to Ackman, his plan would help the Trump administration maximize value for taxpayers, avoid the risk of mortgage spreads widening, and give the U.S. Treasury a clear mark-to-market value for its holdings in both companies.

Ackman's firm, Pershing Square, isn't exactly a passive observer here. The fund holds over 210 million common shares across Fannie Mae and Freddie Mac combined, making it the largest common shareholder in both entities. That's real skin in the game.

The hedge fund manager suggested the deal could wrap up before the calendar flips to 2025, "meeting the expectations of all stakeholders." That's ambitious timing, but Ackman isn't new to bold moves in this space.

Earlier this year, he floated the idea of merging Fannie Mae and Freddie Mac into a single entity. The rationale? Cut costs, simplify the housing-finance system, lower mortgage rates, and unlock shareholder value. Classic Ackman—think big, streamline operations, create value.

The timing aligns nicely with the Trump administration's search for ways to make housing more affordable. That effort includes exploring a proposed 50-year mortgage option, though critics warn such extended terms could saddle borrowers with significantly more long-term debt.

If Ackman's proposal gains traction, it could fundamentally reshape how Fannie Mae and Freddie Mac operate and how the housing market functions more broadly. With his firm's massive stake and the administration's focus on affordability, this isn't just another investor pitch—it's a proposal that could actually move the needle.