​The Updated Background Paper on Annulment provides new data and updated charts and tables concerning developments in case law on annulment from August 2, 2012 through April 15, 2016. It considers 37 new annulment proceedings, 22 new annulment decisions and 19 new decisions on the stay of enforcement of an award issued since the original Background Paper was published in 2012. The paper is the most up to date and comprehensive source on ICSID annulment.

The statistics described in the paper demonstrate that the rate of annulment has declined in the past 3 decades and is currently at 3 percent for the period from 2011 to present. Overall, out of 228 awards, 10 have resulted in partial annulments and 5 in full annulments.  Almost half of those awards have been rendered since 2011, resulting in 2 partial annulments and one full annulment. State-applicants have prevailed in 60 percent of all annulments while claimants have prevailed in the other 40 percent of all annulments. This corresponds to the percentage of annulment proceedings instituted by respondents (54 percent) and claimants (40 percent), with 6 percent of all annulment proceedings instituted by both parties.