Quick answer
It’s more nuanced than a flat yes or no. Ohio law generally doesn’t hold a social host automatically liable for injuries caused by an adult guest who became intoxicated at their home. But liability can still arise if a host knowingly served alcohol to a minor, or if a host knew a guest was already intoxicated and continued serving them in a way that contributed to a later injury.
Umbrella coverage matters here regardless of how the underlying liability question resolves, since defending a claim, even one you ultimately win, carries real cost that a standard policy’s limits can be strained by on their own.