The PTAB continues to be a highly popular venue for patent validity challenges, with final written decisions in post-grant proceedings being largely concentrated in the fields of electrical and mechanical engineering. This suggests a consistent trend in the types of technologies frequently challenged before the Board.

Click here to view the image.

The USPTO allocates each post-grant proceeding to a Technology Center based on which art unit and technology center the patent was examined in during prosecution. The top three technology centers for IPR and CBM final written decisions as of February 1, 2015, are 2800 (Semiconductors, Electrical and Optical Systems and Components) with 41 decisions, 3600 (Transportation, Construction, Electronic Commerce, Agriculture, National Security and License & Review) with 41 decisions (of which 15 are CBM final written decisions, which accounts for the largest share of CBM final written decisions in any technology center), and 2100 (Computer Architecture Software and Information Security) with 32 decisions.

By contrast, technology centers 1600 (Biotechnology and Organic Chemistry) and 1700 (Chemical and Materials Engineering) combine for less than 20% of the final written decisions issued thus far.