In its latest AIA trial statistics report, the PTAB has indicated that 160 petitions for inter partes review (IPR) were filed in May. This represents the most IPR petitions filed in a month since last June.
Source: USPTO
Prior to the spike in new IPR filings last month, the number of new petitions had been trending down recently, with 114 petitions filed in March and 88 petitions filed in April. There were also three post grant review (PGR) petitions and three covered business method (CBM) petitions filed in May.
In April, the Supreme Court decided Oil States, finding that IPRs do not violate Article III or the Seventh Amendment to the U.S. Constitution. The increase in IPR filings last month may indicate a renewed level of confidence in AIA trial proceedings after Oil States. The complete PTAB trial statistics report can be viewed here.