I have a dozen NIB reels of Ampex 407 that I bought from some guy off the net 7 years ago. Never got around to opening one until today. Tried one out today and, yup -- you guessed it -- it's sticky. And I thought at the time that I had really done my homework and that the stuff I had bought was safe.

Well, at least I only paid $67 for the lot postpaid, so I didn't get burned too badly. Guess I'll chuck the tape and keep the reels and boxes.
FYI, these were manufactured in Redwood City, California. The barcode label on the box says 94084 -- I take it that means it was manufactured in '94? The logo is across the bottom of the box, so whether it's in the middle or at the bottom is not a reliable indication of whether the tape is sticky or not.
Honestly, I'd stay away from any Ampex-branded tape at this point, unless it's the so-called "voice grade" red-oxide stuff that is known not to have this problem.