Do figures still take damage from poison if they have invincible?

Edit: Nvm, found it

Nope. Half damage is ignored, 0.5 rounded up is 1, 1 is ignored.

For further reference for invincible, you half the amount (say 3) to 1.5 then round it up (to 2) and ignore that much so you take 1 damage

You ignore half and always round up. Since the amount being ignored is what is calculated, it will always benefit the figure taking the damage.

The others are right, but I wanted to add that even for those special Poisons that deal penetrating damage, they would have no effect against someone with Invincible unless it dealt 2 damage (which only a couple figures can do).