As subject, is collectioncodes dot com a valid reseller site?
[Edited by moderator to remove the actual link. Let's not drive their SEO by having the link here!]
Seems extremely unlikely they are legit. They don't publish a reseller ID or any real contact details. Notice also they don't sell any subscriptions to the current versions, only serial numbers for defunct ones, at too-good-to-be-true prices. I would strongly advise against buying anything from them. You'll be risking your money and your computer if you purchase pirated software.
To good to be true, confirmed!!
On behalf of Adobe …
No, they are not a legitimate Adobe Authorized Reseller. Neither Adobe nor any Adobe Authorized Reseller are selling new licenses for download copies of CS6 software. No CS6 software (or for that matter any non volume-licensed Adobe software) allows for three installations thus this either cracked software (with potential malware) or illegally “unbundled” volume licenses from the past (which Adobe has been revoking access to when found).
As noted above, “too good to be true prices” and lack of any contact information should be immediate red flags.