Brazil has 3rd poly civil union …
From http://polyinthemedia.blogspot.com/2015/12/and-another-civil-union-of-three.html :
This is Brazil’s third união poliafetiva — a poly family becoming officially registered as a civil union — that seems to have made the news. This does not mean multi-marriage is legalized in Brazil. As with the previous groups, the three swore out a document at a city clerk’s office saying they meet the legal criteria for a civil union, including living together long-term and intermingling finances. The statement was notarized to establish that the civil union exists. This entitles them to some marriage-like rights.
See the full story here.