Goldman paid up to make itself invulnerable.

FORBES: Magazine Article

Stealth does not make an aircraft completely invulnerable to enemy forces.

CENTERFORSECURITYPOLICY: Center For Security Policy

Though their size would make them an easy mouthful for a shark or a grouper, their poisonous spines mean they are more or less invulnerable.

ECONOMIST: A heartening tale of business and the environment