In 2009, the US Treasury Department’s Office of Foreign Assets Control (OFAC) blacklisted an individual named Kursad Zafer Cire. Mr. Cire was believed to have run a network that facilitated the sale of nuclear technologies to countries such as Iran, Libya, and North Korea. He was a known bad actor. But from October 2009 to April 2013, PayPal continued to allow payments to be made to Mr. Cire. On March 25, 2015, PayPal agreed to $7.7 million in fines for this and other infractions including processing payments to Sudan, Cuba and an organization in the UK believed to support Hamas. At the time, PayPal had screening technology, yet it was under-employed. And in some exceptional cases, employees had been notified of the condition but continued to allow payments to be made.

http://techcrunch.com/2015/04/12/behind-paypals-foreign-assets-violations/