Last month, it was reported that a Joker sequel was in development, with Joaquin Phoenix, Todd Phillips and co-writer Scott Silver all expected to return. However, that report was soon debunked, and Phillips later clarified that while he and Phoenix have talked a little bit about a hypothetical Joker 2, no deals had been signed and nothing had been officially cemented. Clearly that hasn’t changed, though that doesn’t mean the idea of moving forward with Joker 2 has been tossed aside either.
Article source: https://www.cinemablend.com/news/2486365/todd-phillips-discusses-joker-sequel-rumors-following-golden-globe-nominations