Activity Vocabulary publication history Date Status 23 May 2017 Recommendation 13 April 2017 Proposed Recommendation 15 December 2016 Candidate Recommendation Snapshot 6 September 2016 Candidate Recommendation Snapshot 12 July 2016 Working Draft 6 July 2016 Working Draft 31 May 2016 Working Draft 15 December 2015 Working Draft 6 October 2015 Working Draft 22 July 2015 Working Draft 29 January 2015 Working Draft 23 October 2014 First Public Working Draft