[skwb]

I don't disagree with anything you're saying necessarily, but a lot of people are conflating my statement of IRB exemption with having an explicit IRB authorization. I guess more to my point is people seem to be failing to understand the role of retrospective research (and I will easily concede that different institutions have different legal interpretations) and how it's an important part of research. Don't get me wrong, you absolutely still have regulations about what you can and cannot do with that data, but saying you need an IRB for everything doesn't match the reality that I've seen first hand.

That said, there's plenty of buying and selling of radiological images for industry development on the second hand market. Now where the line of "research" vs. "industrial" work is, well that's something I would leave to legal council. But as you said any sort of "altering" of clinical outcomes is a clear IRB is required zone like DL based recon.