In a significant legal decision, the Federal Circuit vacated a $20 million jury verdict in the case of Rasmussen Instruments, LLC v. DePuy Synthes Products, Inc. This ruling, dated October 6, 2025, underscores the essential role of assignment clauses in patent enforcement.
The crux of the matter lies in patent ownership, which extends beyond mere invention to encompass the legal right to enforce the patent. This right is heavily influenced by the specific language contained in assignment agreements and similar legal documents.
The case began when Rasmussen Instruments filed a lawsuit against DePuy Synthes in October 2020, alleging infringement of two patents, U.S. Patent Nos. 9,492,180 and 10,517,583. Initially, a jury sided with Dr. G. Lynn Rasmussen, awarding him considerable damages after finding that DePuy had infringed the patent.
However, following the trial, DePuy challenged the verdict, asserting that Dr. Rasmussen had failed to substantiate his claim of patent ownership. The court ultimately agreed, stating that Rasmussen Instruments lacked standing to sue because it did not own the patents at the time of the lawsuit.
In examining the history, Dr. Rasmussen had assigned his rights to the Zen Instrument, used in orthopedic surgeries, to Wright Medical in 2006. The assignment agreement defined “inventions” in a manner that included future improvements made by Dr. Rasmussen.
Although Rasmussen and Wright Medical entered into settlement and license agreements in 2013, neither document included an explicit reassignment of patent rights back to Dr. Rasmussen. Consequently, the court determined that his attempt to assign variations of the Zen Instrument to Rasmussen Instruments was invalid, as he did not hold the necessary patent rights.
The ruling emphasized that implied reassignment of patents is inadequate; clear and explicit language is essential for establishing ownership. The original 2006 agreement utilized self-executing language that did not require further action for ownership transfer, meaning that without an express assignment, Dr. Rasmussen had no rights to enforce against DePuy.
This case serves as a crucial reminder that assignment clauses are vital components of patent rights management. They should not be treated as mere formalities but as foundational elements that can determine the outcome of patent litigation. Companies are advised to prioritize the clarity of their intellectual property agreements and maintain a documented chain of title to avoid similar legal pitfalls.
To mitigate risks, organizations should:
- Review all current and past assignment, license, and settlement agreements to ensure explicit patent ownership is clearly defined.
- Consult legal professionals to revise any agreements lacking clarity in assignment clauses.
- Establish procedures for verifying patent ownership prior to initiating any infringement litigation.
- Keep thorough records of patent assignments and related agreements for future reference and enforcement purposes.
