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Examining Patent Examination

By Mark A. Lemley and Bhaven Sampat

The United States Patent and Trademark Office (“PTO”) receives more applications today than it ever has before. What happens to those applications? Patent prosecutors all have stories and personal experiences. Until quite recently, however, this sort of “anecdata” was all that was available, because the law prevented anyone from ever finding out what happened to patent applications that did not ultimately issue as patents.

That changed in 2001, when the PTO began publishing data on pending applications, and when the Patent Application Information Retrieval (“PAIR”) system allowed the public to track the fate of those applications in real time. In this paper, we use those changes to report—for the first time ever—systematic data on the fate of applications submitted to the PTO. We are able to confirm much received wisdom, but also to offer some surprising results.

Posted in Articles.

May 19, 2010 Cite: 2010 Stan. Tech. L. Rev. 2