09/03/2026
More AI adventures in IP…the 5th circuit just refused to amend a defendant’s motion to add prior art references uncovered using an AI patent search app.
In Pacem IP Holdings, LLC v. Maxim Lighting International, Inc., the district court denied Maxim’s motion, ruling that the availability of a new search tool does not excuse a party from explaining why it could not have found the alleged prior art earlier through reasonable diligence.
In a backhanded way, this may be an endorsement for using AI patent search tools early and often, because the real issue was whether the defendant did a diligent search before the filing their pleadings, since the newly (AI) discovered references could have been found and filed as part of their timely filed invalidity argument. The court didn’t care that the AI tool didn’t exist when Maxim’s pleadings were due.
The AI search tool in question was created by PatentVest, Inc., but Maxim alleged it wasn’t available until May 2026. Maxim ran searches on May 18 and 19, and PatentVest returned fourteen candidate references on May 26 and 27, including a 2012 U.S. patent application publication by Fiene and a 2010 Canadian patent by Su. Maxim identified the Fiene and Su prior art references as “potentially highly material prior-art references requiring detailed analysis” on or around June 2, and then prepared supplemental claim charts, serving amended contentions on June 25, and then moved for leave to amend. Maxim’s motion was denied, because “[t]he critical issue is not when [the party seeking to amend] discovered [the] information, but rather, whether they could have discovered it earlier had it acted with the requisite diligence.” The Court continued: “Defendant does not explain why it could not have discovered the Fiene and Su patents with reasonable diligence prior to the April 13, 2026 deadline, notwithstanding the use of an AI tool.”
As a practical matter, AI tools are becoming increasingly easy to find and use, and many government entities provide access to them at no cost. See, e.g., WIPO’s online search page: https://patentscope.wipo.int/search/en/structuredSearch.jsf and pull down the “Search” tab to find the option for AI assistance. As always, we recommend that you carefully review anything found or generated with an AI tool and record when and how each AI tool was used. The legal consequences arising from using AI tools and filing AI generated materials is not what we’d call “well settled”, so we’ll keep watching this space.
This patent search tool allows you not only to search the PCT database of about 2 million International Applications but also the worldwide patent collections. This search facility features: flexible search syntax; automatic word stemming and relevance ranking; as well as graphical results.