The Courthouse News Service has a case that makes one wonder who would spend eight-figure sums on art from someone sharing office space with them or leaves so many high-value objects lying around:

Alexander Komolov says he shared an office on East 16th Street with defendants David Segal and Mohamed Serry, who used several shell companies to cover up their fraud. Komolov also sued Artique International, Pacific Platinum, David Segal Antiques, Artique Multinational, and Segal & Segal Holding. […] Komolov says that in fall 2009, Segal and Serry sold him what they called a Monet, titled “The House of the Artist,” and a Renoir, “Girl in the Garden.” Komolov says he paid $15 million for the paintings, and in December paid more than $1.5 million for silver Russian antiques. Komolov says he used his company, High Value Trading, a co-plaintiff, to make the purchases.
When Komolov discovered that the paintings and antiques were forgeries, he says Segal and Serry refused to return the money. Komolov adds that in March 2010, Segal and Serry stole valuable items from the office that they shared. He claims that Segal and Serry refused to return a $500,000 sapphire ring, a $450,000 emerald necklace, and $10 million worth of paintings, including a Picasso.

Bogus Art Cost Him Millions, Man Says (Courthouse News Service)