Fortress Iron v. Digger Specialties — Federal Circuit Holds Patents Invalid When Missing Coinventor Cannot Be Located

Background

Fortress Iron developed a pre-assembled vertical cable railing system for outdoor spaces, collaborating with two Chinese companies for manufacturing and quality control. While Fortress’s owner originated the idea and an employee prepared initial sketches, employees of the quality control company, HuaPing Huang and Alfonso Lin, contributed critical design refinements. Fortress obtained two patents listing only its owner and employee as inventors, omitting Lin and Huang. Fortress later located Lin and successfully added him as coinventor through the administrative procedure in 35 U.S.C. § 256(a). However, Huang left his company in 2016 without leaving contact information and could not be found. Digger Specialties, the accused infringer, moved for summary judgment arguing the patents were invalid for incorrect inventorship.

Court’s Holding

In an opinion authored by Judge Lourie and joined by Judge Hughes and visiting Chief District Judge Kleeh, the Federal Circuit affirmed summary judgment of invalidity and denial of Fortress’s motion to correct inventorship. The court addressed a question of first impression: what happens when a patent owner acknowledges that an individual is an omitted coinventor but cannot locate that coinventor to provide the notice and hearing that Section 256(b) requires. The court held that an omitted coinventor is a “party concerned” under Section 256(b) who must receive notice and an opportunity to be heard before inventorship can be corrected. Because Huang could not be located to receive that notice, the statutory precondition for judicial correction was not met, and the patents remained invalid for incorrect inventorship.

Key Takeaways

• Inventorship accuracy is critical: patents with omitted coinventors face invalidity if the error cannot be corrected through the statutory mechanisms in Section 256.
• An omitted coinventor qualifies as a “party concerned” under Section 256(b), meaning they must receive notice and an opportunity to be heard before a court can order correction of inventorship.
• Companies collaborating with foreign partners on product development should maintain contact records and inventorship agreements from the outset to avoid this scenario.
• This case of first impression creates a new risk factor for patents arising from collaborative development, particularly with overseas contributors.

Why It Matters

This precedential decision has significant implications for collaborative innovation, especially in global supply chains where inventors may be employees of foreign partner companies. It establishes that losing track of a coinventor can render a patent permanently invalid, with no judicial workaround available. Patent practitioners should ensure all potential coinventors are identified, properly listed, and contactable before filing. Companies should implement inventorship tracking and assignment protocols in their development partnerships, and maintain updated contact information for all contributors.