The Chemical patent reference article from the English Wikipedia on 24-Apr-2004
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Chemical patent

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A chemical patent is an important source of technical and bibliographic information. Chemical patents are different from other sources of technical information because of the generic, Markush structures contained within them, named after the inventor Eugene Markush who won a claim in the US in 1925 to allow such structures to be used in patent claims. These generic structures are used to make the patent claim as broad as possible.

Chemical patents are particularly important in the pharmaceuticals industry where they are used to protect the large investments that are necessary to develop drugs.