Is there a way to do this? I want to make sure I have all of them.

Gonna say, pipboy and Fallout wiki... That should do it...

You can check it in Pip boy. Go to stats, then perks. All the perks you have will be listed, including companion perks.

To be more specific, they are listed with all other perks in Perks sub-tab of Stats tab.

But you need to know what you are looking at, they aren't labelled as companion perks, probably why the above poster cryptically referred to using wikia.

Hope that is more helpful...

Its in your pip-boy under stats i think you have to scroll thru the list. and it will say what perk based on compainion

lol they all came at once...

Yeah sorry, didn't mean to be a [censored]. It's just so generic... Same procedure for most games in this category

Though... Fallout might be in a category of its own?

It just so freaking awesome