An obligation to provide a legal defense against a claim or proceeding when the governing contract, policy, and applicable law require it. It is distinct from the ultimate obligation to pay a judgment or settlement.
A duty to defend is a duty to provide a legal defense when the contract, policy, pleadings, and governing law require it. It is not automatically the same as a duty to indemnify—pay a settlement or judgment.
California Civil Code section 2778 supplies default rules for an indemnity contract unless the parties show a contrary intent, including a duty to defend proceedings within its scope. Insurance duties arise under the particular policy and the law that applies to it. In the General Star decision, the Eleventh Circuit affirmed a defense duty on the allegations and policy exclusions before it; the ruling did not decide that every alleged loss was indemnified.
Read the defense provision, exclusions, reservation-of-rights correspondence, and actual complaint together. The exact policy and jurisdiction decide a specific claim.