For instance
https://www.chase.com/ccp/index.jsp?..._Business_9893
Always yields coupon codes beginning in 3546360
Whereas
https://www.chase.com/index.jsp?pg_n..._Business_9898
Always yields coupon codes beginning in 3546852
Under no circumstances will two coupon codes from the same series ever work even in different years because it will say you have already received the promotion. But usually coupon codes from different series WILL work. I'm not saying that is the reason but it is a definite possibility.
I did get a xerox copy of my coupon in my welcome pack.