Is there an API (preferably PHP based) or another means of checking a use-inputted email address against a list of known email honeypots or other email-address related spam stopping techniques?
Context: I'm working on a system to handle contacts for our clients. It'll eventually interface with Verticalresponse or similar. I want to check all incoming contact email addresses to be sure they're legit and not a purchased list.
You may not find such a database, or a PHP interface. Project Honeypot alone has 62,782,527 trap addresses on their monitor. That's 62 million addresses.
Anyone can make a spam trap. Check for example these references to get a picture of the futility of detecting honeypot addresses.
So what can you do to check that your customers' lists are legitimate? Use an check list for evaluating list contents. If you see anything like removethis, or any such common strings fooling spam harvesters, the list you're looking is probably not a good one. Also, a DNS check for the existence of any records for the domain is also a good way to see to which addresses it is possible to try to deliver mail. The DNS check won't tell you if your client has bought the list or not, but it will at least allow you to disregard those recipients.
