Who actually owns my Apple ID?

One of the problems I have is dealing with all my email addresses and the various Internet Service Providers.

When I bought my iPad, I had to obtain an Apple ID from the Apple company. I could not use another email address and ID.

Therefore is the Apple ID my personal property? Is it something that I now own?

If I quit Apple and go with a different product can I continue to use the " "@icloud.com email address indefinitely?

I would be interested in a legal opinion on the ownership of the Apple ID. Hopefully there are lawyers in the community that understand this issue. For example, if I sell my Apple product, does my Apple ID have to be deleted? Or can I continue to use my email address with another hardware product?