We don't have very many rules, but providing your real/legal name on your membership is one of them, and we do take it seriously.
If you lose access to your membership, the first step in our recovery process is providing a government-issued photo ID matching the name on the membership. For that to work, we need your legal name. If you entered a fake name or an organization name or "Thus-and-such Webmaster" when you signed up, you're typically screwed.
If you real name and legal name differ, we ask for both. We'll set the legal name aside for ID verification and use your real name for all other purposes.
We're absolutely fanatical about our privacy policy. We won't give your name to anybody unless somebody shows up with a judge's signature. In some cases, not even then. If you don't trust us with your name, you probably shouldn't trust us with your content.
Requesting a real/legal name also helps people avoid the most common signup mistake.
If you sign up with a name that isn't a person (i.e., a club/company/organization/role name), or if we have any other reason to believe you've given a false name, we will ask you to fix it. If you refuse, we'll ask you to show a photo ID matching the name you provided (if we're not sure). If you don't, we may be forced to suspend your ability to make further deposits and eventually terminate your service.
If you are an existing member who has given us an incorrect name, please see this entry in the Member FAQ to fix it before it's too late.