Are schema or document definitions covered by the document or software terms?
Check the actual schema or DTDs for a specific license. Otherwise, while schemas and DTDs are frequently part of our specifications and seemingly fall under the document copyright terms, you may use them under the W3C Software License. The software license requires that you include/retain the copyright attribution and that you indicate any modification that you make. In the case of DTDs and schema, you must indicate your change by changing the namespace and/or public identifier so to distinguish your altered version from the W3C version. We further appreciate a couple sentences regarding who made the modifications, when, and what changes were made — a common software documentation practice. We expect to revisit this topic as meta-data schemas become an increasingly important part of W3C specifications and as the meta-data schema definition capabilities of XML and RDF advance.
