There’s been another development in the ongoing patent dispute between Stratasys and Bambu Lab.
In fact, the continuing patent battle has taken a rather strange turn.
Less than three weeks after a Texas jury awarded Stratasys US$27.6M in damages for Bambu Lab’s infringement of four patents, the US Patent and Trademark Office’s Patent Trial and Appeal Board (PTAB) found challenged claims in four Stratasys patents unpatentable as obvious.
Two of them — US9168698 and US10556381 — are the force detection patents involved in the Texas verdict. Together, those patents accounted for about US$2.8M of the jury’s damages award.
The third, US11886774, covers detection and use of 3D printer configuration information. The fourth, US10569466, covers tagged build material, including a printer reading information from a tagged material supply and using it to determine printing parameters.
Both of those patents belong to the second Stratasys lawsuit against Bambu Lab, which has not yet gone to trial.
At first glance this seems impossible. How can a jury find that Bambu infringed patents that another US government body shortly afterwards says should not have been patentable?
The answer is that the two proceedings are doing completely different jobs.
PTAB is a tribunal within the USPTO composed of administrative patent judges with legal and technical training. Bambu challenged the Stratasys patents through inter partes review, or IPR, a procedure that allows issued patent claims to be reconsidered using earlier patents and published prior art.
That is quite different from defending an infringement lawsuit in federal court.
An issued US patent enters a federal infringement case with the presumption that it is valid. The accused infringer has to overcome that presumption with “clear and convincing evidence”, a relatively high standard established by US patent law and affirmed by the Supreme Court.
At PTAB, the challenger has to demonstrate unpatentability by a “preponderance of the evidence”. In other words, the evidence merely has to tip the balance toward the claim being unpatentable.
That means the Texas jury’s decision is sometimes not portrayed as it really is unfolding. The jury did not independently confirm that the Stratasys patents were actually valid. Instead, it determined that Bambu had not met the level of evidence required to prove the claims invalid in that specific legal proceeding.
PTAB subsequently examined the patentability question under its own lower standard of evidence and reached a different conclusion.
That leaves at least one piece of the US$27.6M verdict in doubt.
Bambu Lab was ordered to pay about US$2.8M for infringement of the two force detection patents, yet PTAB has now determined the claims involved in that award to be unpatentable.
That does not automatically eliminate US$2.8M from the first case. The PTAB decisions can themselves go through further review and appeal, while the district court verdict is also subject to post-trial proceedings and appeal. The two legal tracks therefore haven’t finished colliding yet. Yes, it’s confusing.
Most of Stratasys’ award is unaffected by these latest decisions. About US$14.2M hung on US9421713, the patent involving purge towers, while another US$10.6M was tied to US7555357, which involved extrusion path generation. Together that’s US$24.8M of the US$27.6M award.
The purge tower patent has also been challenged at PTAB, but Stratasys prevailed in that proceeding. Bambu is appealing that result.
Meanwhile, the findings against US11886774 and US10569466 could complicate Stratasys’ second lawsuit before that case even reaches a jury. As you can see, this is by no means over. Appeals and additional proceedings could keep both cases in the mix for quite some time.
Patent cases are notoriously difficult to follow, and this ongoing scenario demonstrates why. Bambu Lab can lose an infringement trial while simultaneously convincing the Patent Office that some of the very patent claims it supposedly infringed should not have survived examination.
No one is paying anyone anything until this is all done.
For now, Stratasys still has its US$27.6M judgment, but US$2.8M of it may fade away.
Via Ex Parte
