Since this has been raised as a major issue in past discussions, I have asked Paul Beame and Donna Cappo for an official response to a third question.
QUESTION 3: Does ACM or SIGACT claim rights to the name “Symposium on Computational Geometry”? Specifically, if the SOCG community votes to end its relationship with ACM and organize an independent conference, will ACM or SIGACT insist that the independent conference have a different name, or that proceedings of the conference are published under a different title?
I specifically requested an answer that represents ACM’s official legal stance; consequently, I expect the answer will take some time.
Added Jun 9: ACM’s conference manual suggests that their answer to Question 3 is likely to be affirmative:
Statement of Understanding – Conference series are considered the intellectual property of ACM. Once ACM sponsors a conference, workshop or symposium, the rights to the event, including without limitation the name, and whether arising now or with respect to the same conference held in the future, are the properties of and belong to ACM. Steering Committees and General Chairs of continuing meeting series are not free to modify sponsorship.
On the other hand, COLT was allowed to keep its name when it became independent in 1999, after 11 years of ACM sponsorship. And there is no indication (yet) that CCC will be required to change its name as a result of declaring independence from IEEE. It’s hard to imagine that ACM would try to organize its own “SOCG” over the objections of the research community that built and maintained it over the last three decades, but stranger things have happened.