Hi . I'm not sure I understand the question. The core_v2_forum.List() API only lists forum applications, not their content. So there isn't a filter for authors when listing forums. However, there is also the core_v2_forumThread.List() API that lists forum threads from applications, and it does accept an optional AuthorId parameter in case you want to only list threads by a certain user. It also accepts many other filtering options.
Hope this helps. If not, please share a bit more about what you're trying to do.
