Recreational drone users no longer have to register their flying machines with the Federal Aviation Administration, thanks to a federal court ruling handed down today, but the hobbyist who filed the challenge says the issue is far from settled.

“I’m concerned, as are other hobbyists, that the FAA will now go to Congress and try to get the authority that they lack,” John Taylor, a Maryland insurance attorney and drone pilot, told GeekWire via email.

The FAA instituted its registration fee for non-commercial drones weighing between 0.55 and 55 pounds in late 2015. By early this year, more than 670,000 operators had paid a $5 registration fee.

Registered operators were required to stick their ID number onto their drones and re-register every three years. Failing to do so could land an operator in prison for up to three years with a maximum criminal penalty of $250,000.

Taylor argued that drones technically qualified as “model aircraft,” and that the FAA was barred from regulating model aircraft under the FAA Modernization and Reform Act of 2012.

In today’s ruling, the U.S. Circuit Court of Appeals for the District of Columbia agreed with the FAA that the rule on registration could improve aviation safety, but sided with Taylor’s argument that the FAA had no statutory authority to enforce that rule.

In a statement, the FAA said it was reviewing today’s ruling.

“The FAA put registration and operational regulations in place to ensure that drones are operated in a way that is safe and does not pose security and privacy threats,” the agency said. “We are in the process of considering our options and response to the decision.”

The FAA did not address whether people who already registered their drones would get their $5 back, but Taylor believes they should.

“I’m not sure yet what the FAA’s plan is for the $3 million to $4 million they’ve unlawfully collected from folks,” he said. “I suspect they may be getting some phone calls.”

Marc Scribner, a transportation policy expert at the Competitive Enterprise Institute who has previously spoken against the rule, congratulated Taylor. “Kudos to John Taylor for fighting for the rights of drone hobbyists and holding FAA accountable for its lawless behavior,” he said in a blog post.

Not all in the drone community see the ruling as a victory, however.

Brian Wynne, president and CEO of the Association for Unmanned Vehicle Systems International, expressed his disappointment and vowed to work with Congress on new safety regulations.

“A UAS [unmanned aircraft system] registration system is important to promote accountability and responsibility by users of the national airspace, and helps create a culture of safety that deters careless and reckless behavior,” he said in a news release.

The drone registration debate is separate from the debate over FAA regulations governing commercial drone operations, such as the delivery systems being planned by Amazon and other companies.

The FAA issued its first batch of rules for small commercial drones last year, and further regulatory actions are expected to address such scenarios as flights over the uninvolved public and flights beyond an operator’s line of sight.

Taylor said he hopes future FAA actions will focus on promoting safety and cracking down on reckless behavior, without tightening down on the activities of law-abiding model airplane hobbyists.

He noted that other regulations are still being contested. For example, drone pilots still have to deal with restricted no-fly zones that include Disney theme parks, big events such as the Super Bowl, and the area around Washington, D.C.

“The FAA contends it’s illegal for me to fly model aircraft within 30 miles of Washington National Airport,” Taylor complained. “They’re applying a post-9/11 regulation written to protect the nation’s capitol from attack by airplanes. It has no rational application to model aircraft.”

Taylor’s not stopping with today’s court ruling. He said he has another petition in the works that focuses on a big question surrounding drones: Who has the right to the airspace in our own backyards?