Aaron Bradley, the markup king, posted on Google+ that Bing updated their structured data documentation to now support ClaimReview. ClaimReview "annotations should be used to convey that the page contains fact check information. This may be used to display enhanced captions on Bing that help convey this information to users."
Google launched something similar, or exactly the same, in October 2016 when all the fake news and facts issues were surrounding the election process. Bing was a bit delayed but now they have it.
Aaron said "while there's been no official announcement yet from Bing, this strongly suggests that, like Google, Bing will start to annotate search results with fact check information." Indeed.
Forum discussion at Google+.