Learn English – What’s the grammar of “Attached” in this email

I have won a prize.

This is win in the present perfect sense.

• Present perfect sense: It means you won a prize in the past, then X, then now. X is not specified here and is not required to be specified.

  • Reasons for X not being specified include emphasis that something's in the past, communicating that something happened outside of the recent past, communicating that a state change is completed and not in progress, and expecting X to be filled in from context.

  • A possible fill-in for X is "the contest ended" or "I actually received the prize."

I heard about him having won a prize.

This is kinda-sorta win in the present perfect sense in gerund forum. It means he has won a prize, but it's converted to a gerund form so it can be an object of a preposition.

I'm sure I made someone with higher rep than me angry at saying that gerunds can have perfect forms. I don't really think gerunds can actually have perfect tenses - because A) they aren't even pure verbs and B) it doesn't work at all with past perfect.

What I think is really going on is something like this:

I am having lunch now.

I am having my nails done.

I am having my car repaired.

A meaning of have is "to take in" or "to receive or undergo an action."

I am having my clothes tailored = I'm receiving the action of "clothes tailored" from someone.

So:

I heard about him having won a prize = I heard about him having undergone the action of "win a prize."

I haven't been there in two years ... I wanted to know about him not having been there in two years = I wanted to know about him not having undergone the action of "being there".