While changes (fine-tuning) to a heuristic system often have unpredictable consequences, additions to URL filtering are absolutely predictable – it will block one spam campaign and nothing else. For example, consider a legitimate newsletter from drugstore.com (a legitimate retailer) that advertises various health products and perhaps has “free” offers. Many heuristic systems will have trouble accepting this as a legitimate email due to “spam-like” content. Because SpamStopsHere almost completely ignores normal content, this email would not be blocked.
Now consider a spammer that takes the drugstore.com newsletter and changes all URL links from drugstore.com to drugstorerx.com (assuming this is the spammer’s domain and website), and then sends this to a huge email list. This would be a heuristic system’s nightmare. First the spammer’s newsletter would likely not be blocked; then after many user reported the spam, the legitimate newsletter would also be blocked in the future.
With URL filtering, only the drugstorerx.com domain needs to be added to the blocking database. If not already in the blocking database, the SpamStopsHere technology would likely add it automatically and then have its 24/7 staff confirm it.
With URL filtering, the legitimate drugstore.com newsletter will never be blocked while the spammer’s newsletter (with nearly identical content) will be blocked 100%. Also, with URL filtering, the anti-spam vendor can determine precisely what will be blocked by policy. For example, the vendor can decide to block all emails that link to pornographic, casino and betting sites. Without blocking even vulgar personal emails, or discussions about casinos.