A federal judge ruled on Friday that the Trump administration can't delay an Obama-era immigration rule that would let foreign start-up founders into the U.S. without a visa.

The exemption for immigrants who create companies and employ Americans was set to go into effect this past July. But the government said at the last minute it would delay its implementation until March 2018.

The National Association of Venture Capitalists and others sued to overturn the delay. On Friday, the U.S. District Court for Washington, D.C., ruled in their favor.

The International Entrepreneur Rule allows immigrant entrepreneurs and their families to remain in the U.S. for 30 months without a green card or other visa and apply for another 30-month extension after that.

The rule, created during the waning days of President Obama's administration, is designed to encourage more foreign entrepreneurs to start companies in the U.S.