Duty to Defend

Summary: It is a long-held axiom that an insurer’s duty to defend is broader than the duty to indemnify. But what encompasses that duty? On what is the duty based: the factual allegations in the complaint, or legal theories of recovery such as negligence, assault, battery, trespass, trademark infringement, defamation, or some other legal theory? Can other evidence or facts not in the complaint be considered? What if the complaint includes allegations obviously not covered by the policy? What if the complaint includes both allegations obviously covered and some allegations obviously not covered?

Further, when does the duty to defend end? What happens when an insurer determines it has no duty to defend only to later learn there was such a duty?