Carl Icahn has a new activist target—Washington.
The man best known for battling some of America's biggest companies is now taking his fight to the nation's capital. In a letter, released Wednesday and sent to several leading members of Congress, the billionaire investor says he's forming a super PAC and pledging $150 million of his own money to push for corporate tax reform.
Icahn said he's targeting "inversions" which occur when a company changes its domicile, often outside the United States, to take advantage of lower tax rates elsewhere.
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"I believe my own commitment of $150 million to the PAC will be more than enough to make voters fully aware of the horrible consequences that will ensue if Congress fails to pass legislation immediately to stop these 'inversions,'" Icahn said.
On CNBC's "Fast Money: Halftime Report," Icahn noted he believed change could come through congressional legislation. He did not say specifically how he would use the money to urge that change, other than to hold Congress "accountable."
"The political arena today is completely dysfunctional," Icahn said.
In the letter, Icahn said as many as 50 companies have left the U.S. over the past few years, representing more than a half-trillion dollars in market value, costing hundreds of millions of dollars in taxes and lost jobs.
"If this exodus is allowed to accelerate, there will be disastrous consequences for our already fragile economy, as well as meaningful and unnecessary job losses," he said.
Icahn contended reform would not only bring those companies' tax money back to the United States but also reduce the threat of them leaving for good.
"I think right now we're not aware of the fact there's a great danger very many companies are going to leave this country," he told CNBC.
The topic is not new to Washington. Last September, the Obama administration, citing a need for "economic patriotism," threatened tougher rules for corporate inversions, but no executive orders or legislation on the issue have yet to be passed.
Icahn sees adding language to the Highway Bill, which is currently being debated in Congress, as an ideal opportunity to address the issue.
The billionaire said he has spoken with Democratic Sen. Charles Schumer and potential House Speaker Paul Ryan about his plan and that both are in agreement.
Central to Icahn's idea is allowing multinational companies to bring funds back from overseas without the threat of "double taxation" — commonly called repatriation.
He cites the more than $2 trillion American companies have parked overseas as evidence that the current tax code is anticompetitive.
"These companies want to bring this money back to the United States, but they choose not to because we require they pay a "double tax" if they do," Icahn said. "We are the only country in the world that does this, and it's counterproductive because it creates an incentive to keep the money abroad."
Icahn is one of the largest shareholders in Apple, which holds more than $100 billion in cash overseas. He told CNBC he did not believe the tech giant would attempt to leave the United States.
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Aside from his own millions, Icahn said he'll attempt to raise even more money from others — making one of Wall Street's most formidable activists a new political force on Pennsylvania Avenue.