It says in the article that Dmitry Rybolovlev (his family's trust to be exact) bought it from Yves Bouvier for $127.5 million in 2013, which occurred soon after Bouvier had purchased it earlier in 2013 for $80 million in a private sale via Sotheby's.

Rybolovlev and Bouvier have been in a legal battle over their business dealings (including the da Vinci sale): https://en.wikipedia.org/wiki/The_Bouvier_Affair

If you want to read a long-form story on Bouvier (which does touch on this situation), I'd recommend this: https://www.newyorker.com/magazine/2016/02/08/the-bouvier-af...