When One Patent Application Begets 10: Today's Hyperproliferative U.S. Restriction Practice

Restriction practice (<i>ie</i>, the restriction of a patent application to prosecution of a single claimed invention (per filing fee)) has been around since the mid-1800s. In recent years, hyperproliferation of restriction requirements, especially in the biotechnology, chemical and software arts, has occurred. It has not been uncommon for the U.S. Patent and Trademark Office (PTO) to assert that a patent application contains 10, 20, even 100 distinct inventions. In fact, the PTO itself recently stated that there had been an application in which the PTO had determined that there were 400,000 distinct inventions. Excessive use of restriction requirements has the potential to stagger a corporate patent budget, because multiple divisional applications must be filed to prosecute all claims, and hence, all "inventions" of the original application. If a company has budgeted for one patent application, it is then faced with filing multiple applications to receive the complete patent coverage that was envisioned. This leads to increased costs of the filing, prosecution and maintenance; multiplication of patents with overlapping subject matter and related claims; shortened statutory patent terms (depending on the timing of filing of the divisional applications), and a question of whether complete patent coverage is truly achieved by compartmentalizing the "invention" into many patents.

27 minute read January 01, 2004 at 11:07 AM
By
Teresa J. Welch, Ph.D.
When One Patent Application Begets 10: Today's Hyperproliferative U.S. Restriction Practice

Restriction practice (ie, the restriction of a patent application to prosecution of a single claimed invention (per filing fee)) has been around since the mid-1800s. In recent years, hyperproliferation of restriction requirements, especially in the biotechnology, chemical and software arts, has occurred.

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