Edwin Southern developed a blotting technique for DNA in 1973, thereby creating a staple of molecular biology laboratory procedures still used after several decades. It became a seminal technology for studying the structure of DNA. The story of the creation and dissemination of this technology, which was not patented and was freely distributed throughout the scientific community, stands as a case study in open science. The Southern blot was developed at a time when attitudes about commercial intrusion into health research were beginning to change and the practical value of molecular genetics was becoming apparent to industry. Interest from industry in fundamental molecular biological techniques meant that scientists began to think about commercial uses of their work even in otherwise "basic" research. The unpatented Southern blot is contrasted with later patented technologies, particularly microarray methods, which were created in the same environment by many of the same people, but which followed significant changes to UK policies encouraging commercialization of academic research and a norm shift friendlier to such commercialization within academic molecular biology. Professor Southern's personal experience illuminates how the technologies evolved, and his views provide insight into how scientists' attitudes about commercialization have changed.