The international transplant community portrays organ trade as a growing and serious crime involving large numbers of traveling patients who purchase organs. We present a systematic review about the published number of patients who purchased organs. With this information, we discuss whether the scientific literature reflects a substantial practice of organ purchase. Between 2000 and 2015, 86 studies were published. Seventy-six of these presented patients who traveled and 42 stated that the transplants were commercial. Only 11 studies reported that patients paid, and eight described to what or whom patients paid. In total, during a period of 42 years, 6002 patients have been reported to travel for transplantation. Of these, only 1238 were reported to have paid for their transplants. An additional unknown number of patients paid for their transplants in their native countries. We conclude that the scientific literature does not reflect a large number of patients buying organs. Organ purchases were more often assumed than determined. A reporting code for transplant professionals to report organ trafficking networks is a potential strategy to collect and quantify cases.