Patent Patent rights expire?

[guestposter]

My grandfather received a patent for rubber asphalt in the mid 70's and my estranged relatives informed me that his patent rights expired in 1992. Is there a predefined time for this and, if so, does 17 yrs sound right? Seems a bit brief to me.

 

[Michael Wechsler]

My grandfather received a patent for rubber asphalt in the mid 70's and my estranged relatives informed me that his patent rights expired in 1992. Is there a predefined time for this and, if so, does 17 yrs sound right? Seems a bit brief to me.

The length of a patent depends upon the type of patent. It's not a brief period of time. You are probably confusing patent with copyright or trademark law, which lasts for a much longer duration.

Utility Patents and Plant Patents last for a maximum of 20 years from the date of the US filing of the earliest non-provisional application. Design Patents last for 14 years from the date issued. No extensions are available.