Activist investor Carl Icahn’s big $50 million bet on Fannie Mae(FNMA) and Freddie Mac (FMCC) brings even bigger guns to the table for investors in the GSEs who want the mortgage giants to pay shareholder profits it owes.

Icahn acquired 6.8 million shares of Fannie and 5.7 million shares of Freddie from Fairholme Funds, court records show. Investor Bruce Berkowtiz of Fairholme also invested early on in the GSEs, and heavily.

Icahn, the billionaire investor head of Icahn Enterprises is known for buying big stakes in companies and then pushing for fundamental management change.

Icahn made the purchases March 11, when both stocks were down – Fannie down 31% and Freddie down 27%.

(Click on the two images below to see where the stocks listed March 11.)

This latest $50 million buy-in puts Icahn on the side of consumer advocate Ralph Nader, CapWealth Advisor CEO Tim Pagliara and dozens of GSE shareholders from 20 states.

The shareholders want recapitalization and their shares before any GSE reform, and only after that should various reform measures be considered.

That’s the position of Pagliara’s Investors Unite.

Investors Unite opposes the current terms of Fannie and Freddie’s bailout agreement with the government.

After Fannie Mae and Freddie Mac were bailed out during the financial crisis and placed into conservatorship, all profits were directed back to the U.S. Treasury.

Now that the full measure of the bailout has been paid back, investors who were put on hold want their stake and rights protected.

In doing this, Icahn is joining an investor campaign against a federal bureaucracy that has nationalized mortgages for the most part.

These investors believe that the government acted outside its aegis and powers when it made Fannie and Freddie remit its near monopolistic profits to the Treasury.