A real estate listing in metro London is the first clue in more than five years to the whereabouts of Bulgarian-born German citizen Ruja Ignatova, 42, the "crypto queen," who is on the FBI's 10 Most Wanted list.  Her penthouse apartment in the London suburb of Kensington, England, went up for sale for $15.5M, which was then downgraded to $13.6M.  Ignatova purchased the property under a shell company called Abbots House Penthouse Limited, based in Guernsey, a noted tax haven.  Ignatova's whereabouts were unknown since 2017 until now and kept out of public records and land registry deeds.  The sale of the penthouse "suggests she is still alive, and there are documents that contain vital clues about her recent whereabouts," said Jamie Bartlett, an investigative reporter who hosts "The Missing Cryptoqueen" podcast. The FBI believes that she traveled with a German passport from Athens, possibly to the United Arab Emirates, Germany, Russia, Eastern Europe, or even back to Bulgaria.  A change in the rules of Companies House revealed Ignatova's possible location as she had to reveal her name on the sale of the apartment.