SAN FRANCISCO (AP) — A federal judge has ordered the Port of Oakland to stop using Oakland International Airport in the San Francisco Bay Area as the new name for its airport as a lawsuit filed by the city of San Francisco is in progress.

San Francisco filed a lawsuit in April over what it considers trademark infringement and asked a federal judge to issue a preliminary injunction, arguing that the airport’s new name is confusing to people wishing to travel to San Francisco International Airport and violates copyright.

U.S. District Judge Thomas Hixson issued an order Tuesday upholding the copyright infringement argument, saying San Francisco spent millions to build its brand. The judge also ordered the Oakland airport to remove all signs bearing the new name.

Port of Oakland spokesman Robert Bernardo said officials were reviewing the decision and considering their options, including appealing.

The Port of Oakland Board of Commissioners finalized in May approval to change the name Oakland International Airport despite objections from San Francisco officials who said the name would create confusion and financially hurt the SFO.

Oakland airport officials said travelers unfamiliar with the area land at the San Francisco airport even if their destination is closer to the Oakland airport across the bay from San Francisco. Changing the name to San Francisco Bay Oakland International Airport will change that, they say. The airport’s three-letter code, OAK, would not change.

“We stand up for Oakland and the East Bay,” Port Commission Chairwoman Barbara Leslie said in a statement after the vote. “This name will make it clear that OAK is the closest major airport to 4.1 million residents, three national laboratories, the nation’s premier public university and California’s wine country.