General Principles and Object of Claims:
Claims are considered to be the most important part of a patent
document. In a complete specification the description is followed
by the Statement of Claims. Since the claims constitute the legal
part for claiming the protection of the patent rights, the
construction of same plays a critical role as it is central to the
evaluation of infringement and validity.
The "Markush" claim is a special drafting manner for
claims in the field of Chemical and Biotech Inventions, which was
first successfully used by the inventor Eugene Markush in a US
patent in 1920, post which claims of this kind are named after his
family name.
A Markush claim refers to a chemical structure by means of
symbols indicating substituent groups. In such a claim, one or more
parts of the claimed compound comprise multiple functionally
equivalent chemical entities.
