Altec isn't the only company that's changed hands/ownership/structuring/location in the last 50 years...

WirRep had roots with Blachford, which had roots with... all the way back to Germany and WWII.

"Secrets" have nothing to do with it. At one time, Aquaplas was a patented product, and trade rights were protected accordingly for the normal period. That period has been over for a long time.

I sincerely doubt that any of it is exactly the "same stuff" as produced 50 years ago... what is? All that matters is that it does the same job (or better).