Quick answer
Often yes, many umbrella policies include personal liability coverage for claims like libel, slander, and defamation, not just physical injury or property damage. This is one of the more overlooked benefits of umbrella coverage, since most people associate it purely with accidents rather than reputational harm claims.
Coverage specifics vary by carrier, so this is worth confirming explicitly rather than assuming, particularly for anyone in a public-facing role, board position, or business capacity where this kind of claim is a realistic possibility.