An influential patent judge recently wrote that “every patent trial lawyer worth her salt brings a challenge to the damages opinions offered by her adversary. Never mind that the percentage of such challenges that succeed is exceedingly small.”

Those challenges are nonetheless likely to keep coming, and Facebook Inc. and its defense lawyers at Cooley just proved that they can work. In a ruling issued on Tuesday—one week before a scheduled trial date—U.S. district judge T.S. Ellis III in Alexandria, Va. disqualified a damages expert proffered by Rembrandt Social Media, a non-practicing entity represented by Fish & Richardson. The expert had been set to testify that Facebook should pay millions of dollars for allegedly infringing two Rembrandt patents relating to social networking, including a patent entitled “Method and Apparatus for Implementing a Web Page Dairy.”

Although Ellis’ opinion redacted the damages figure proposed by Rembrandt’s expert, he made clear that it was too high. “Rembrandt’s expert claims damages ‘far in excess of the contribution of the claimed invention to the market,” Ellis wrote in his ruling. “His testimony would unreliable…and allowing such inflated numbers before a jury would be prejudicial.”

Ellis instructed Facebook and Rembrandt’s lawyers to meet on Friday “to discuss issues regarding the upcoming trial, including the effect of the Court’s recent order excluding plaintiff’s damages report and related testimony.”

It’s tough to fully recover from disqualification of an expert witness right before trial. In September, we told you about an NPE that voluntarily withdrew an infringement case after its damages expert got disqualified right before trial.

If the case does disintegrate, Facebook will undoubtedly be very pleased. Rembrandt is a well-funded NPE with a compelling story. It acquired its patents in early 2013 from the widow of a now-deceased computer programmer named Joannes Jozef Everardus Van Deer Meer. According to Rembrandt’s initial complaint, “at the time when the Word Wide Web was in its infancy, Van Der Meer was a pioneer in the development of user-friendly Web-based technologies.”

Rembrandt’s lead lawyer, Fish partner Thomas Melsheimer, is one of the most sought-after trial lawyers in the country. Ars Technica has more background on the case here.

Michael Rhodes and Heidi Keefe of Cooley represent Facebook. Rhodes declined to comment.

Melsheimer didn’t immediately return a request for comment.

Jan Wolfe is a senior reporter with The Litigation Daily, a Recorder affiliate.