use of w3c logo, did-doge

I noticed in the previous that the w3c logo was altered, with the "c"
changed to a "d" for doge

https://spruceid.github.io/did-doge/docs/w3d.png

I'm in the process of creating a did draft, and I was wondering to what
extent the w3c logo can be reused, an in which context

Can w3c logo be used in community group drafts, or must it first be in the
registry?  Can it be altered etc?