A tentative sale — and possible demolition — of the old Federal Reserve building in downtown Seattle has been nullified by a federal judge.

A federal judge has struck down a tentative deal by the Federal Reserve Bank of San Francisco to sell its old downtown Seattle building to an undisclosed buyer.

The Fed, which moved its local office to Renton in 2008 and months later agreed to sell the old building, violated procedural requirements of federal environmental and historic-preservation laws, U.S. District Judge Robert Lasnik ruled Friday.

His ruling came in a lawsuit filed by a committee led by consultant Art Skolnik, a former state Historic Preservation Officer. The group feared the unnamed buyer would demolish the 60-year-old, six-story building and build a skyscraper on the site, between Madison and Spring streets on Second Avenue.

Before entering into the sale agreement, the Fed obtained a ruling from Seattle’s Landmarks Preservation Board that the building did not qualify for protection.

But Lasnik wrote that the Fed had erred in not considering alternative uses for the building, and in not preparing an environmental-impact statement on the building’s future until after the sale agreement had been signed.

“The judge’s decision is a landmark reminder to government agencies that they cannot cut corners on their obligations under the National Historic Preservation Act,” Skolnik said. “The bank has the opportunity to do the right thing and ensure that this part of our city’s architectural heritage is preserved.”

Eric Pryne: 206-464-2231 or epryne@seattletimes.com