Perhaps, you are right in that the mistake should have been caught earlier than five years ago (2010 filings have it correct). However, upon further thought, I've decided that skimming/proofing over the docs wasn't likely the issue. English being a second language was the more likely issue years ago and it got picked up and reposted continually.
Read the following that I'm quoting with permission from BigKahuna in my pm's. He's likely posted it somewhere on the board, but, no time to search:
Thankfully, the error was corrected five years ago in the 2010 SEC filings.