Can a chemical compound be claimed by its characteristics instead of its structure?

Yes, chemical compounds can be claimed by their characteristics when the structure is unknown. The MPEP 2173.05(t) provides this option:

“A compound of unknown structure may be claimed by a combination of physical and chemical characteristics.”

This approach is supported by legal precedent, such as Ex parte Brian. When structural information is unavailable or incomplete, describing a compound by its physical and chemical properties can be an effective way to claim it in a patent application. This method allows inventors to protect their discoveries even when full structural elucidation is not possible or practical.

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Topics: MPEP 2100 - Patentability, MPEP 2173.05(T) - Chemical Formula, Patent Law, Patent Procedure
Tags: Characteristic-Based Claims, chemical compounds, patent claims, Unknown Structures