Markush structures are molecular skeletons that contain not only specific atoms but also include one or several placeholders each representing a broad set of chemical (sub)structures. They are used by pharmaceutical companies to claim a large class of compounds without the necessity of writing out every fully defined single chemical entity in a patent application. (For instance, the Markush structures claimed within patent EP 0810 209 contain a total of 10^16 different compounds resulting from all possible permutations within the Markush structures.) After summarizing the ongoing policy debate regarding the use of Markush structures in patents, this paper provides first quantitative evidence regarding the use Markush structures in the pharmaceutical industry and their effects on important outcomes in the patent prosecution process.
Contact: Marina Chugunova