A broker or agent always owes these duties to the person they are representing (their principal): Loyalty, Obedience, Disclosure, Confidentiality, Reasonable Care and Diligence, and Accounting. These duties are inherent in all agency relationships and enforced by all courts of law in the United States.
A trustee has fiduciary duties, whether they are a trustee for an IRA or a living trust. Some of the duties are formalized in written contracts; others are implied by law. p 81
The term fiduciary is defined as of relating to or involving a confidence of trust. Fiduciary duties include: confidentially, undivided loyalty, obedience, reasonable care and diligence, full disclosure, and accounting. Regardless of whether the duties owed in a particular state are traditional, common law fiduciary duties, or are statutorily defined, they are owed to any principal/client.