I was actually wondering something similar. If one starts a thread, does one have an obligation to 'host' the thread? by that I mean going back and reading posts and responding to at least some of them....
That's different than 'owning' a thread. I don't think that one can control the life of a thread, but I do wonder if the thread starter has an obligation to at least check back and reply (at least once!)
Not having started many threads in seven years, I am not certain of proper etiquette.
But to answer the original question, no, I don't think that anyone can fully 'own' a thread. 'Host' it maybe, but 'own' it no.