HGF Presents
Patenting Polymorphs at the EPO
September 2025
Video overview:
Novelty and Inventive Step
Prior art must necessarily lead to the claimed polymorph to be novelty destroying
Watch out for inherent disclosures in prior art—methods may implicitly produce polymorphs even if structural data isn’t provided.
Provide experimental evidence if needed to show prior art does not produce the claimed polymorph.
Emphasize any advantages or unexpected properties of the polymorph, ideally supported by data, to support an inventive step, in the application.
Highlight advantages of the polymorph versus other forms.
Clarity
Provide a clear, precise definition of the polymorph.
Clearly define the crystalline form using appropriate physicochemical parameters and measurement conditions.
Sufficiency
Clearly describe how to prepare the polymorph. If preparation requires seeding crystals, disclose how to prepare the seed in the application.