Last week, Microsoft completed a legal attack on two large and quite nasty botnets by obtaining a court order transferring 23 domain names to Microsoft’s control. The botnets went down and the Internet was a better place for it. But in doing so, Microsoft also took out the world’s largest dynamic DNS provider using a dangerous legal theory and without any prior notice to Vitalwerks Internet Solutions—the company that runs No-IP.com—or to the millions of innocent users who rely on No-IP.com every day.