Content Filter: Blocking Spam
You can use the content filter to block spam, especially that which complies, or attempts to comply with legislation requiring that bulk emailers provide a means of removing addresses from the spamming list.
Create a new Policy and add keywords such as the following to cover a wide range of "remove" phrasings:
remove in the subject line
"remove" in the "SUBJECT"
"remove" in the subject line
remove in the "subject" line
remove list
Per Section 301, Paragraph (a)(2)(C) of S. 1618
Disable Case sensitive comparisons in the Content Filter page to have the filter trigger a match for remove, REMOVE, ReMove, etc.
You can create additional policies like the one above according to actual samples taken from your own spam (or that of your users).
See also: