Make sure you send in only one rebate form/upc/receipt per envelope.
I wasn't sure after reading the fine print, so I called. The guy actually told me that I needed to send in 3 different envelopes, one envelope per rebate request.
This is dumb. The original (not printed from the website) rebate form states:
"... request form along with the UPC symbol(s) from the applicable product(s)..."
(Can't load up TDK's website right now for some reason to look at the online rebate form.)
To me, this means one request per envelope, but with 3 UPC symbols allowed.
Anyhoo, make sure you send them in separately.
Oh yeah, circle the TDK CDR on your receipt too. Not sure if they'll reject it if you forget that.