Examining US patent examinations

Stanford Professor Mark Lemley is probably the most prolific academic writer on IP at the moment. In his latest (well, latest when I hit post – it might well be his second latest paper by the time the post is published) paper, he takes an empirical look at US patent examination.

For the paper, he and co-author Bhaven Sampat of Columbia followed every patent application filed in January 2001 and published by April 2006 – a total of 9,960 applications. Using the USPTO’s PAIR database, they were able to collect a vast amount of data on the applications.

Unsurprisingly, the large majority of examinations – 86% - started with a non final objection.
Perhaps more surprising is that 1,833 applications that were “finally” rejected at some stage nonetheless resulted in issued patents. The chance of having your patent application finally abandoned is only slightly greater for those applications that got a final rejection than those that didn’t (26.5% for those with a final rejection compared to 24.6% in the overall sample).

85% of the patents that do issue, issue with amended claims. 66.1 percent of applications which were amended after a final rejection are patented, versus 29.0 percent of those that were not amended. A cynical cat would note that this is something every patent attorney could have told you: you can always get a patent, the question is, what for? But, as Prof. Lemley notes, the fact that most patents are granted with amended claims shows that the USPTO is serving its role as a gatekeeper potentially better than its critics acknowledge: it is not enough to point out that 70% of applications result in granted patents to conclude that it is “too easy” to get a patent if 85% of the patents are granted with amended – presumably limited – claims.

27% of the applications have continuations or a RCE (Request for Continued Examination). The number of continuations varies greatly between industries (see table above). Again, the result pretty much confirms the conventional wisdom – biotech applications are well known for continuations.

Working draft of the paper here.