Unitalen Acted for Client to Successfully Invalidate Part of Opposing Party's Patent for Invention for Injection Pen, Paving the Way for Product Commercialization for the Client

November 19, 2025

Recently, in a patent invalidation proceeding, Unitalen, acting on behalf of a client, successfully secured partial invalidation of a patent for an invention related to an injection pen held by the opposing party, thereby paving the way for the client's product commercialization.

Case Brief

Previously, Unitalen's client was planning to launch an injection pen product. During a Free to Operate (FTO) analysis conducted on this product, Unitalen identified a Chinese patent for invention relevant to the product (hereinafter referred to as the "patent involved patent"). To prevent the patent involved from obstructing the commercialization of the injection pen product, Unitalen initiated an invalidation proceeding against the patent involved upon accepting the entrustment.

The patent involved protects an injection pen. Its technical solution comprises multiple interconnected mechanisms such as a dose display mechanism, a drive mechanism, and a clutch mechanism, which makes the technical solution complex. Furthermore, the patent involved has an early filing date, and its family patents have been granted by multiple patent offices. Meanwhile, the technical terms are inconsistent, which significantly increases the difficulty in reviewing prior art documents and feature matching.

After accepting the entrustment of the client,  the Unitalen team carefully reviewed the examination history of its family patents, found the closest prior art from the examination history, and determined the optimal combination of evidence by combining the above findings with the result of the search, thereby partially invalidating the patent involved and achieving the client's business objectives.

Summary of Highlights

In this case, the Unitalen team approached the matter from both the examination history of the family patents and the invalidation search. When checking the examination history of the family patents, the Unitalen team conducted a supplementary search on relevant patents by searching the citations. When performing the invalidation search, the Unitalen team, drawing on experience from prior injection pen cases, prioritized the prior patents of several major injection pen manufacturers and identified suitable documents for combination, thereby improving search efficiency.

 

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