"if it was known or used by others in this country before the date that the applicant made his/her invention, a patent cannot be obtained".
Mind you, they don't seem to apply this very consistently.
I was originally pointing out a fact lest others be led astray, but I'm not going to reply further.
However, 10ren's statement seems to be backed up pretty well by the USPTO site - if you have already gone public or sold your invention, no patent for you. I'm not sure why you think it is incorrect.
Cheers