"Ron Bean" > wrote in message
...
>
> "Del Cecchi" > writes:
>
> >The microwave popcorn bag is patented.
>
> Patents only last 17 years. How long have they been around?
>
> BTW I've tried taking the Powerpop out before it stops popping
> and so far the inserts do seem to last longer (too soon to tell
> how much longer). I typically get several pops after I've taken
> it out of the microwave.
>
>

It appears, from searching Delphion.com, that the first bags were patented
in the 70's, but that what we know and love didn't come along until the mid
80's. Followup patents continue until today.

del cecchi
>