During the Cold War, East Germany had very little money, because the Soviet Union had stripped the country of its assets. What they had plenty of were political prisoners, so there was a clandestine program to sell these prisoners -and their family members- to West Germany. Journalist Gavin Haines wrote about the practice for the BBC.
"Figures do vary, but between 1964 and 1989 there were approximately 33,700 political prisoners that were sold," Haines says. "In addition to that, they obviously had lots of family members. So there was an additional 250,000 people who were sold."
It's a huge number. German media wrote about the practice, but few people in the English-speaking world knew about it until Haines' article came out. He says both sides, East and West, weren't interested in having the story come out. Why? It makes both countries look terrible.
NPR has an interview with Haines in which he describes the secret practice of buying political prisoners from East Germany.