SPC Clarifies Prosecution History Estoppel, Overturns Non-Infringement Ruling in Rose Packaging Patent Case – (2024) SPC IP Civil Final No. 405
Summary:
The Supreme People’s Court (SPC) overturned a first-instance judgment in a patent infringement case involving a German packaging company, clarifying the application of the prosecution history estoppel principle. The court held that a patentee’s emphasis on distinguishing its invention from prior art during prosecution, based on the rigidity of its material, did not constitute a clear disclaimer of all deformable plastic materials. The SPC found infringement, reversed the non-infringement ruling, and awarded damages to the patentee, Rose Plastic AG.
I. Key Facts
Patent Involved: Invention titled “Polygonal Sliding Packaging” (Patent No. ZL201310204227.3), owned by German company Rose Plastic AG.
Procedural History: Rose Plastic sued two defendants for patent infringement. The first-instance court (Guangzhou Intellectual Property Court) dismissed all claims, applying the prosecution history estoppel doctrine. It held that the patentee, during the substantive examination, had distinguished its invention by stating its material was “rigid and bend-resistant,” thereby disclaiming the elastic plastic material used in the accused product. Rose Plastic appealed to the SPC.
Technical Dispute: The core issue was the interpretation of the claim limitation “the two hollow bodies are made of a rigid and bend-resistant material.” The patent’s inventive concept lies in a structural design that enables opening/closing without relying on wall deformation. The accused product is made of plastic.
II. Key Holdings
Proper Construction of “Rigid and Bend-Resistant Material”: The SPC ruled that the term must be interpreted in the context of the invention’s purpose. The patent’s specification aimed to overcome the defect of prior art, which required wall deformation. The claimed “rigid and bend-resistant” material refers to materials that do not undergo significant deformation under normal use, not to materials that are absolutely non-deformable. Relatively rigid plastics are not excluded.
Rejection of Overly Broad Application of Prosecution History Estoppel: The SPC clarified that a patentee’s arguments made during prosecution to distinguish prior art do not automatically constitute a clear and unambiguous disclaimer of an entire category of technical solutions. In this case, Rose Plastic’s emphasis on “rigid” material was to highlight the structural difference from prior art that relied on elastic deformation, not to expressly abandon all plastic materials capable of any deformation. Without such clear abandonment, the prosecution history estoppel principle should not be invoked to unduly narrow the protection scope.
Infringement Found: Applying the correct claim construction, the SPC found that the accused product’s unlocking mechanism did not rely on wall deformation. Therefore, the plastic material used fell within the scope of “rigid and bend-resistant material” as properly construed.