Fannie Mae (FNMA 0.34%) has had an incredible run in 2013. Its stock is incredibly up almost 1000% on the year. But there is one critical thing investors may be missing about this stock.

Fannie Mae headquarters in Washington, D.C.  Photo: Flickr/Future Atlas.

Its goals are not your goals
Fannie Mae and Freddie Mac are the two government-sponsored entities, or GSEs, that are principally responsible for providing liquidity in the mortgage market by guaranteeing and buying mortgages from banks. Yet following the spectacular collapse of the housing market in 2008, Fannie Mae was placed into conservatorship by the Federal Housing Finance Agency, or FHFA, as it received a total of $116.1 billion in government bailout funds.

So what does that mean for investors? Well, the FHFA states plainly, "As conservator, the [FHFA] assumed all the powers of the shareholders, directors, and officers, with the goal of preserving and conserving the assets and property of Fannie Mae and Freddie Mac."

Read that statement again.

The FHFA is in complete control of Fannie Mae, and its goal is simply to preserve and conserve its assets.

In the most recent annual report, the position is repeated, noting that "[t]he conservatorship is a statutory process designed to preserve and conserve our assets and property and put the company in a sound and solvent condition."

As conservator, its only aim is to "preserve and conserve," with the ultimate outcome being that the company is "sound and solvent."

Think about that for a moment. When you're buying stock in a company, you aren't gambling on the success of it, but taking ownership in it, with the explicit understanding that the managers and directors will operate in a way that seeks to maximize the value of the return on your investment. Yet in the case of Fannie Mae, it exclusively operates with its conservator's interests in mind, not those of its shareholders.

Consider Berkshire Hathaway (BRK.A -0.76%) (BRK.B -0.69%), Warren Buffett's empire that has been one of the best investments of the past half century. Care to guess what the line item at the bottom of the income statement is titled? "Comprehensive income attributable to Berkshire Hathaway shareholders" (emphasis mine). And at Fannie Mae? "Net income (loss) attributable to Fannie Mae" (emphasis, again, added).

In fact, Buffett even notes that the company's "long-term economic goal ... is to maximize Berkshire's average annual rate of gain in intrinsic business value on a per-share basis." That's a far cry from the "preserve and conserve," "sound and solvent" mentality that those at the helm of Freddie Mac hold.

It isn't even so much that Fannie Mae is operating with its own best interests in mind, as doing so clearly has generated results. It's that Fannie is completely open to the reality that it simply doesn't care about its common shareholders, which is what you are when you buy into the company.

The following are all quotes from its most recent annual report:

"Because we are in conservatorship, we are no longer managed with a strategy to maximize shareholder returns."

"[E]very dollar of earnings that Fannie Mae and Freddie Mac generate will be used to benefit taxpayers for their investment in those firms."

"The conservatorship and investment by Treasury have had, and will continue to have, a material adverse effect on our common and preferred shareholders."

"The future of our company is uncertain."

It is not only open about its position of not operating with the best interests of the shareholders in mind. It is, in fact, adamant about it. Although many have sought to change this course of action, the federal government and those at Fannie Mae have given no indication that it will happen at all, much less anytime soon.

When you buy stock in a company, you're hoping that those directing the company will see to maximizing your return. But when you buy stock in Fannie Mae, you're willingly putting your money behind a company that plainly assures you it will not.