The American definition of a "check" is extremely simplistic and notably does not define a list of things that exclude it from being valid. It can say "sample"

The American definition of a "check" is extremely simplistic and notably does not define a list of things that exclude it from being valid. It can say "sample" all over it or "not valid" and it's technically still a legal check. Once in a while those "sample" checks issued by junk mailers actually work because the bank fails to check these things: http://www.sfgate.com/news/article/Playing-With-Money-How-a-95-093-35-junk-mail-2588766.php http://www.sfgate.com/news/article/Playing-With-Money-How-a-...