MetLife sued a panel of regulators led by the Treasury secretary on Tuesday to fight its designation as “systemically important,” making it the first financial company to go to court over the issue since the government started singling out so-called too-big-to-fail institutions in an effort to stem any future financial crises.

The regulatory panel, known as the Financial Stability Oversight Council, has been deciding which companies qualify as systemically important, an authority given it under the Dodd-Frank financial overhaul law. The goal is to prevent the kind of domino effect that swept the financial system in 2008, when the troubles of a few important companies threatened to topple countless others unless taxpayers provided a giant bailout.