The Act catches anyone who, for compensation, is in the business of advising others about securities. Registration goes to the sec above an assets-under-management threshold and to state regulators below it, and the vehicle for both is form-adv.
Courts read a fiduciary duty into the Act's antifraud provisions: duties of care and loyalty, with full and fair disclosure of conflicts and informed client consent. That standard is stricter than the brokerage regulation-best-interest rule.
Operational rules do the real work in examinations. Custody rules dictate who may hold client assets and when a surprise audit is required, the marketing rule governs testimonials and performance claims, and the compliance rule requires written policies under a chief-compliance-officer.
Related: registered-investment-adviser, form-adv, fiduciary-duty, chief-compliance-officer, regulation-best-interest