I was sealing around air leaks in the attic and realized one can light had holes in it. My impression was that means the can was not IC compliant. I took the trim off and it does say IC on the sticker. Is it normal to have holes in these cans?
Yes it's normal.
The holes do not go all the way through but to a space that is covered by another can that does not have holes and can be in contact with the insulation.
Just in case there is also a thermal safety switch within the fixture that automatically turns off the light when too much heat from the bulb has been trapped and the temperature to rise to a certain point. Once the fixture has cooled, the switch turns the light back on again.