Police in Barobo district wrote on Facebook on Saturday that documents found aboard the boat revealed the body was German citizen Manfred Fritz Bajorat.
His remains, partially preserved by the salt water and sea air, were found seated at the vessel's writing desk next to the radio gear. Bajorat's head was resting on his arm as if he were taking a short nap.
The mummified remains of Manfred Bajorat pictured aboard his yacht. Photo: Barobo police
"The way he's sitting at the table, it's likely that he had a heart attack in the best case," forensics expert Dr. Mark Benecke told Bild, "but that's just speculation."
Meanwhile, police told the tabloid that while no wallet was found on the yacht, the fact that other valuables were still on the boat pointed away from a high-seas robbery.
"There is no evidence of a second person having been on board," a police spokeswoman said. "No weapons were found either".
"It's a riddle for us," Barabo deputy police chief Mark Navales told Bild.
Boat drifting for months?
Fishermen discovered the boat drifting half-submerged in the sea on February 25th during a routine fishing trip off the east coast of Mindanao, the second-largest island in the Philippines. They found the body when they boarded to investigate.