How was Denny's Favorite 50 developed?

A question for Denny, How was ‘Denny’s Favorite 50 developed?’

Was it some wild yeast that you happen to capture? Is it a relabeled variety of yeast? How did Wyeast get hold of it?

Apologies in advance if I’m asking too sensitive a question.

Thanks for saving me the effort, Nighthawk!