kale77in writes "I was going to direct this question to the Australian Arts Law Centre, and probably still will, but I'm sure they're very busy and I'm sure that someone here must have bumped up against this issue already. I have not found it addressed in the CC FAQ. I have a website which is oriented around the study of Ancient Greek. Much material relevant to this study (texts, lexica, etc) was published in the 1800s; it is now out of copyright and readily available from archive.org and similar sources; but much of this material could use an upgrade and users will have up-to-date contributions of their own to make. I'm writing a system that allows user entry, correcting, searching, commentary, tagging, redistribution and so on, of such material." Read on for the questions this raises about licensing, attribution, and copyright.Kale77in continues: "Here's my issue: I would like everything to be under Creative Commons BY-SA — I can say 'same as Wikipedia' and this will encourage participation and confidence. The question is who should own the copyright of user-created data. I'd like the copyright to be held by the submitter. But I've no interest in enforcing anything more than pseudonymity for the users. Now I understand that copyrights can be held pseudonymously; but how does this allow attribution as required by CC-BY-SA? Is it enough for an author of a derivative work to reference the page on my site where the pseudonymous copyright holder grants the license? Does the end user need to be able to contact the copyright holder for additional rights? Is this a road through a minefield, so that I should just bite the bullet and, like Wikipedia, make a foundation to hold and license the copyright for collaborative works? But that costs money to administer; for a small non-profit venture is it best to just chill and take resort in persuading the users to make everything public domain? Or does a special User Agreement allow some way to gain the benefits of CC licensing (= endless reuse, and no hassle) without losing pseudonymity? But then, won't a complex upfront agreement hinder participation?"