By Charles Sanders, Anant Saraswat and Nathanial McPherson, Latham & Watkins LLP (May 5, 2017, 10:44 AM EDT) -- As the America Invents Act approaches its five-year anniversary of going into effect, inter partes review has become a standard tool for defendants in patent infringement actions, while post-grant review is just starting to be used. To date, petitioners have filed thousands of IPR petitions but only about 50 PGR petitions. PGR is only available for patents arising from applications containing claims with an actual priority date on or after March 16, 2013.[1] As more issued patents qualify for PGR, parties increasingly will have a choice between IPR and PGR. This choice needs to be made early by parties considering preemptive challenges to patents that may restrict freedom to operate in the future because PGRs must be filed within nine months after patent issuance. This article explores the opportunities afforded by IPR and PGR for preemptive challenges and strategic considerations for choosing between them....