I don't remember exactly who it was, but one of the inkjet places. I used a coupon that was on the company's home page, but didn't get credit for the purchase because the coupon wasn't on Ebates. Kind of a bummer, too, because the rebate would have been about $5.00. I found this from Ebates' FAQ:
"When using coupons and specials at any of our merchants, we can only guarantee your cash back rewards with the use of coupons that are listed on the Ebates site."
So it sounds kind of hit or miss. I'm glad you've gotten credit, and hope it continues for everyone.