WASHINGTON — A decision by Blue Origin to withdraw most of the claims in a contested patent represents a near-term victory for SpaceX, but might not be the end of a dispute between the two companies regarding reusable launch vehicle technology.

In a “Final Judgment and Decision” issued by the U.S. Patent and Trademark Office Aug. 27, the Patent Trial and Appeal Board approved a request by Blue Origin to cancel 13 claims in a patent covering the landing of rocket stages on oceangoing vessels. The board had agreed in March to a SpaceX petition for an “inter partes” review of those claims by the board.

The request by Blue Origin to cancel the claims ended the review of what is known as the “’321 patent,” after the last three digits of the patent number. “Here, Blue Origin has requested cancellation of all the claims on which trial was instituted, hence, no claims will remain for trial,” the board noted in its decision. “In view of the cancellation of claims 1-13 of the ’321 patent, the entry of final judgment adverse to Blue Origin is appropriate.”

The patent, titled “Sea landing of space launch vehicles and associated systems and methods” and issued to Blue Origin in 2014, originally had 15 claims. The board ruled in March that two of the claims were not subject to inter partes review because they were too vague for the board to decide if SpaceX had a “reasonable likelihood” of winning a review on those claims.

SpaceX petitioned the patent board in August 2014 to review the ’321 patent, citing “prior art” — information that existed in the public realm before the patent — similar to claims in the Blue Origin patent. That included academic papers published in the 1990s that showed a similar approach to landing rocket stages on platforms at sea or other bodies of water. SpaceX has attempted to land the first stage of its Falcon 9 rocket on its “autonomous spaceport drone ship” twice, most recently in April.

The board’s decision makes the ’321 patent effectively unenforceable, one patent attorney noted. “This is the end of their ability to enforce that patent,” Andrew Rush, president of 3-D printing company Made in Space and an attorney who has closely followed the case, said in a Sept. 2 interview.

Rush noted, though, that while the board’s decision is a victory for SpaceX, Blue Origin is not giving up on the overall patent. Earlier this year, the company filed what’s known as a “reissue patent application” that seeks to amend the original patent. “This is a patent owner saying, ‘There’s a problem with my original patent. I want to rewrite my patent and turn in the old one,’” Rush explained.

Such a strategy, he said, is not uncommon among patent holders in similar disputes. In those cases, the patent holders choose to withdraw the claims of their original patent while simultaneously filing a reissue patent application with revised claims intended to avoid the prior art that triggered the dispute. “It looks like they’ve retreated, but they haven’t given up by any means,” he said.

Reissued patents, which are granted their own number, are relatively rare: while patent numbers recently crossed the 9 million threshold, the number of reissued patents is only in the tens of thousands. They can also take years to review: a May 2015 study by intellectual property law firm Wolf Greenfield found that the average waiting time for patents reissued in 2014 was three and a half years.

Rush expects one of two outcomes if and when the U.S. Patent and Trademark Office issues a revised patent. If the revised claims are so narrowly defined as to exclude SpaceX’s approach, he said it’s unlikely the company would contest it. If, however, there is some overlap, “we’ll see the conflict start up again.”

That, however, could be years away, Rush noted, given the waiting time for reviewing reissue patent applications. “There’s a good chance this conflict will be on the back burner for the foreseeable future.”