In the beginning of 2015, the Shanghai Customs Anti-Smuggling Bureau discovered a number of coins in the domestic market that been previously issued and listed in overseas markets. After an investigation, police named a man surnamed Chen as their suspect.

On May 15, 2015, the Shanghai Customs Anti-Smuggling Bureau placed this case on file and officially started an investigation. On July 6, Chen flew to Shanghai from Hong Kong without making any customs declarations. Customs officers searched his bags and found 2,116 gold coins and 216 silver coins. Some of the commemorative coins were very limited editions.

The investigation revealed that Chen had been in the commemorative coin business for a long time. He was the owner of a coin company. From 2013 to 2015, Chen had purchased great numbers of overseas commemorative coins and smuggled them into Chinese mainland. One of the coins that he smuggled was a gold coin only issued in 2013, year of the snake, which weighed 10 kilograms and was worth 78,000 US dollars (about 5 million yuan). There are just 18 coins of this edition in the world, and the coin could sell for 6 million yuan in the Chinese market.

According to the law, commemorative coins issued overseas have to go through imported goods customs procedures in order to reenter the domestic market. Chen has been arrested for smuggling.