Many Google AdWords professionals who are taking the AdWords exam to become certified as a Google AdWords partner are getting confirmations that their certificate expired over 46 years ago, specifically on December 31, 1969. The December 31, 1969 bug is a typical coding date bug, so no need to worry, it is a bug.
Here is a screen shot of the notification people get when they view their partner profile and check their status of their AdWords certification:
It reads, "Congratulations! You're AdWords certified. Your certification is valid through Dec 31, 1969."
Google responded to several folks on Twitter saying this is a bug the tech team is working on fixing:
@iambradlarabell Hi Brad, our technical team is aware of and currently working on this issue. (1)— Google AdWords (@adwords) September 20, 2016
So just wait it out, all will be fine.
Forum discussion at Twitter.