Who owns Cat in the Hat?

Could you please clarify who exactly owns the intellectual property rights to the beloved character "Cat in the Hat"? Is it the original creator, Dr. Seuss, or has the ownership transferred to a publisher or other entity over time? I'm curious about the legal ownership structure surrounding this iconic character and how it has evolved since its inception. Additionally, are there any licensing agreements in place that allow for the use of the "Cat in the Hat" in various forms of media and merchandise?