I'm pretty sure your pets don't get them. Just you. It can make it very difficult to soft-cap them for defense or resistance.
Only things that go to your pets are things you can slot in their power (ie. Soulbound Allegiance: Chance for Build Up, Achilles' Heel: Chance for Resistance Debuff) or the four Uniques that affect pets (Edict of the Master +Defense, Sovereign Rights +Resist, Expedient Reinforcement +Res, Call to Arms +Def)...
I think. Don't quote me on that.
50s: Yumi Eryuha-Arch/Energy, Mirria-Thugs/Dark, Meyami Kitsuna-Claws/SR, Celesta Seusen-SS/Invuln, Lady Mirriella-Illusion/Empathy
Arc 503982 "Dimension Xi Epsilon 22-10" Part one of a multi-part arc.
Easy way to check: get a cheap set pair with a bonus type that would show on your own Combat Attributes panel, put it in a pet, summon that pet, and finally look for the bonus in the pet's Combat Attributes...
You cannot buff your pets' values except by enhancements like Edict of the Master +Defense and the like.
First time I made a Mastermind and played it seriously was maybe three years ago, maybe longer, before IOs came out. Then I went Blue side exclusively, with the exception of one Brute and one Stalker. Now I'm back and Masterminding, and loving my Bots/Traps.
My question is, all those lovely little set bonuses you get via sets, are they passed on to your babies as well? Specifically, Gaussian's Synchronized Fire-Control and the like, which have a chance for build up. Who's getting that? Me, my pets or both?
Pardon my ignorance.