The answer is provided by the block chain, on which the information of the entire supply chain is stored. The start-up company Opensc uses the technology to prove ecological and social standards. Every fishing boat is tracked by GPS and satellite communication. Each fish is given a so-called RFID tag. This tag is removed later during processing. All kinds of information is stored from the tag onwards: Where the fish was caught, the name of the boat, the captain. If the fish is cut up and packed, the data is transferred to QR codes. In this way each individual fillet can be assigned to the original fish. The fish is also already available in selected German supermarkets.