Season 5 Episode 9: Mace Tyrell and a representative from the Iron Bank are discussing the ethics of charging interest for loans. It is noted that high interest payments are seen by some as distasteful and there are threats of legal actions for higher interest payments. Throughout history, in fact, there are times where certain loans and interest charges have been illegal, including medieval Europe. Alvin Roth, who won a Nobel Prize in Economics for his work on market design, discusses the history of repugnant markets. Sometimes the exchange of goods is considered illegal and therefore a market cannot exist. For example, it is illegal in many parts of the world to buy horse meat.