Lifesteal can generally not heal off of allies and wards. For some reason, Insatiable Hunger can, as the only source of lifesteal.

Repro:
1. Lose health as Broodmother
2. Cast Insatiable Hunger
3. Attack some wards or allies

Result: Insatiable Hunger's Lifesteal heals from wards and allies.

Expected: Like every other source of Lifesteal, Insatiable Hunger should not heal off of wards and allies.