The referenced notice, together with other legalese, is available at . Although it doesn't specifically forbid sub-licensing, it does say "The above licenses are limited to only those rights required to implement the Specification and no others. That is to say, Adobe grants only those rights in the above patent(s) necessarily practiced to implement the Specification, and does not grant any rights not required to implement the Specification." The Adobe language seems to be saying exactly the same thing as the MS language. I think one must conclude that either .doc and .pdf are both open formats or they are both closed.