Foreign publication leads to patent invalidation
It’s not easy out there for a patent owner. Even after a patent is granted, an owner can find the patent’s validity challenged if it hasn’t thoroughly searched for “prior art.”
That’s what happened to one telecommunications company: in an inter partes review (IPR) proceeding, the competitor alleged that prior art anticipated the invention, invalidating the patent. The case illustrates the low standard for the admission of late evidence in IPR proceedings and provides guidance on when a printed publication qualifies as potentially invalidating prior art.
PTAB shelves patent
Telefonaktiebolaget LM Ericsson (Ericsson) owned a patent for methods of receiving and processing wireless signals at multiple frequencies without requiring separate receiver components for different frequencies. TCL Corporation filed two IPR petitions for certain claims in the Ericsson patent.
Under IPR, the Patent Trial and Appeal Board (PTAB) can reconsider and cancel an already-issued patent based on limited types of prior art, namely patents and printed publications. The PTAB here found the challenged patent claims obvious, largely based on an article published in a German technical journal. Ericsson appealed.
Declaration isn’t overdue
Ericsson’s appeal focused on whether the article was — as required to invalidate a patent — publicly available more than one year before the patent application date of July 1, 1997. (Under current law, a patent is barred if an invention was disclosed in a printed publication any time before the application date.)
The relevant journal bore the date of May/June 1996 but wasn’t available in the United States until October 1996. TCL submitted a sworn declaration from a librarian at a German university that the article was catalogued and publicly available there in June 1996, though.
Ericsson contested the PTAB’s admission of the declaration. It cited a regulation that requires a party seeking to submit new or supplemental information more than one month after an IPR has begun 1) to show why the information reasonably couldn’t have been obtained earlier, and 2) that consideration of the information would be in the interests of justice.
The PTAB determined that the librarian’s declaration satisfied the regulation. It noted that the librarian was the only person TCL found with personal knowledge of the 1996 recordkeeping procedures at the library who was willing to sign a sworn declaration and travel to the United States to be deposed.
Ericsson also claimed it was prejudiced by the admission of this evidence because it had been developing its defense against other prior art that the board discarded after accepting the article as principal prior art. The court pointed out, though, that the PTAB gave Ericsson adequate opportunity to respond and produce contrary evidence. It concluded, therefore, that the interest of justice weighed on the side of admitting the declaration.
Evidence checks out
Ericsson then argued that, even if admissible, the declaration didn’t establish the date of public availability. A reference is publicly available if it has been “disseminated or otherwise made available to the extent that persons interested and ordinarily skilled in the subject matter or art, exercising reasonable diligence, can locate it.”
The librarian declared that the journal had been in her library’s collection since 1963. The specific issue was inventoried June 18, 1996, and accessible to the public after a processing time of one to two days. She provided copies of the index card that recorded the library’s acquisition of the journal and the library’s entry for the specific issue.
Ericsson contended that the index card was insufficient evidence of public availability. But it provided no evidence to counter the librarian’s declaration, the date on the journal, or the library’s records showing receipt of the journal and its shelving.
The court found substantial evidence of public availability. It held that the PTAB didn’t abuse its discretion accepting the article as a prior art reference and affirmed the obviousness finding.
Research pays off
The results in this case make clear the importance of conducting exhaustive prior art searches before filing a patent application. By overlooking the article in the German journal, Ericsson not only lost its patent and the related competitive advantages, it also incurred years of costly litigation.
Telefonaktiebolaget LM Ericsson v. TCL Corp., No. 18-801, Nov. 7, 2019, Fed. Cir.
The plaintiff’s alternative argument fails, too
The plaintiff in Telefonaktiebolaget LM Ericsson v. TCL Corp. (see main article) also argued that, even if the prior art was publicly available at the relevant time, it actually “taught away” from the patented invention, specifically its use of a frequency divider for phase shifting. A reference teaches away when it would:
Ericsson contended that the article didn’t teach that frequency dividing should be used because it discusses the disadvantages, as well as the advantages, of doing so. The Patent Trial and Appeal Board found — and the court agreed — that though the article cited a disadvantage, it didn’t suggest frequency dividers would be ineffective. The article didn’t “criticize, discredit or discourage the technological efficacy of a frequency divider for phase shifting.”