Sealand currently has no regulations regarding copyright, patents, libel, restrictions on political speech, non-disclosure agreements, cryptography, restrictions on maintaining customer records, tax or mandatory licensing, DMCA, music sharing services, or other issues;
child pornography is the only content explicitly prohibited. At the present time, child pornography is not precisely defined; HavenCo is obeying rules similar to those of the United States, specifically a prohibition on any depiction of those under 18 in a sexual context.
http://www.havenco.com/