OFF Corps is sponsoring four catalog projects. Each catalog has specific vetting rules for the URLs that it contains.

• The Public Domain Repository requires that all included URLs reference works that are public domain in at least one country.
• The Library of Citizens On-Line requires that all included URLs reference legally made copies donated by non-anonymous citizens.
• Publius requires that all included URLs be anonymously signed catalog references.
• The Copyright Management Information Registry requires all included URLs to contain CMI and to be signed by a registered copyright holder.