Lockhart's announcement envisioned that the Company would eventually be returned to profitability, and the conservatorship would be lifted. He made clear that the conservatorship would be run with an eye toward attracting additional private investment to the Company, noting that "some of the key regulations will be minimum capital standards, prudential safety and soundness standards and portfolio limits." According to Lockhart, the purpose of the new regulations was "so that any new investor will understand the investment proposition."
Bear in mind, that the parties are not suing Fannie Mae’s board or management, but are defending the company against its conservator, the FHFA. Thus, the defendant is the Federal government. Here is a definition of a derivative lawsuit from Wikipedia:
"A shareholder derivative suit is a lawsuit brought by a shareholder on behalf of a corporation against a third party. Often, the third party is an insider of the corporation, such as an executive officer or director. Shareholder derivative suits are unique because under traditional corporate law, management is responsible for bringing and defending the corporation against suit. Shareholder derivative suits permit a shareholder to initiate a suit when management has failed to do so." http://en.wikipedia.org/wiki/Derivative_suit