Associate specific PGP subkeys with specific UIDs

Question

It seems to me like PGP keys contain a "collection" of UIDs and also contain a collection of subkeys. Moreover, there doesn't seem to be a way to add comments to a subkey.

Is there any way for me to say:

"If you send encrypted emails to [e-mail], use the this subkey. But if you send encrypted emails to the address [e-mail] use this other subkey."

In this example, [e-mail] is also owned and operated by me, but perhaps I want to allow access by other people to this one without giving them the key to my personal email address. I could post this information on my website, but I'd rather make that information clear in the key itself.

Is it possible to do this? Or is the "standard way" to just create a completely separate identity and keyring for [e-mail]?

Answer 1

No, this is not possible; there is no solution specified and I don't know of any clients supporting anything implementation-specific or discussions on standardizing such a feature. Furthermore, most implementations even don't allow to manually select a subkey to encrypt to (so you even can't tell anybody to manually use a specific subkey, but the newest one will be used.

I could imagine a solution using notations, and also but be grateful if one existed.