Coincidentally with this activity, I also realised that some of the people to whom I was sending cultures were using the cells for vaccine development and potentially production of vaccines. It occurred to me that this might mean my being liable for some accident that one could only imagine, that the cells I would be sending to people would be used for a product or a test that would hurt or even kill somebody, and I became alarmed when I realised that this might happen.

And so I printed a little label that I put on every culture that I sent out that essentially said – of course, I had no legal authority for this but at least I had gone as far as I could go – and it said, in red letters, actually, that I was not responsible for whatever use the cells in this culture would be used for. That actually was the beginning of what later became a universal document in the United States, and probably worldwide, called: A materials transfer document, which, as the name implies, it became not only fashionable but legal subsequently when cultures were sent to people that they sign a materials transfer agreement, which is what it is actually called, an MTA. And that has become… is now standard operating procedure. But I pioneered that back in the early '70s – '70, '71.