The Humane Society of the United States has long been one of the most vocal critics of the fast food industry in the country. But for the past week, the animal rights organization has taken on a surprising new role vis-a-vis fast food: major investor.

Is this a case of "If you can't beat 'em, join 'em?" Has the Humane Society gone turncloak? Not exactly.

Instead, the advocacy group's latest move -- a $4000 investment in Apollo Global Management, the private equity firm that owns Carl Jr's and Hardee's -- is motivated by a desire to influence animal welfare policies at the fast food chains from the inside. The Humane Society's 325 shares of AINV represent a tiny share of the company's total outstanding stock: just .00016 percent. And Apollo does a lot that's completely unrelated to the fast food industry. So it's not like the Humane Society will be making big bucks off a business it normally opposes. Nor is the HSUS share of the company big enough to demand serious policy change at Carl Jr's or Hardee's.

But what the share does do is allow the Humane Society to present resolutions at Apollo shareholder meetings. Most companies require an investment of at least $2000 for that privilege, but a $4000 investment gives enough of a buffer that the HSUS will maintain its standing even if the stock's value declines. Anna West, a representative from the group told the Huffington Post that the Humane Society's priorities were to ensure better animal welfare at the facilities that supply the pork and eggs for Carl Jr's and Hardee's.

But a resolution isn't even necessarily in the works. "We are hoping that we can accomplish our goals without presenting a resolution," West said. "We are working not only with Apollo Group Management, but also with individuals at Carl Jr's and Hardee's."

The group's advocacy is unlike to fall on deaf ears in this case. In 2007, Carl Jr's and Hardee's both agreed, after talking to PETA, that they would try to stop working with vendors that had poor records on animal cruelty.