Investment Adviser Fiduciary Duty Under the Advisers Act of 1940

The investment adviser fiduciary duty under the Investment Advisers Act of 1940 requires anyone paid to give investment advice to act in your best interest and to put your interests ahead of their own. The Advisers Act itself never uses the word “fiduciary.” The Supreme Court read the obligation into the statute in 1963, and the SEC broke it into its two working parts in a 2019 interpretation: a duty of care and a duty of loyalty. Together they govern what your adviser recommends, how trades get executed, how conflicts are handled, and how long the obligation lasts.

Where the Duty Comes From

Section 206 of the Advisers Act prohibits an adviser from employing any scheme to defraud a client and from engaging in any practice that operates as fraud or deceit on a client or prospective client.¹ The language is broad, and the Supreme Court gave it shape in SEC v. Capital Gains Research Bureau, Inc. (1963), holding that the Act reflects a congressional recognition of “the delicate fiduciary nature of an investment advisory relationship” and an intent to eliminate, or at least expose, all conflicts of interest that might lead an adviser to give advice that is not disinterested.² The case involved a newsletter publisher who was quietly buying stocks before recommending them and selling into the price bump. The Court did not require proof that any client had actually been harmed. The failure to disclose the conflict was itself the violation.

The SEC’s 2019 interpretation confirmed the two-part structure and made a critical point: disclosure alone cannot satisfy the duty. An adviser who tells a client about a conflict and then acts against the client’s interest has still breached the standard.³

What the Duty of Care Requires

The 2019 interpretation identifies three components of the duty of care: giving advice in the client’s best interest, seeking best execution for trades, and monitoring the relationship over time.³

Advice That Fits the Client

Before an adviser recommends anything, the adviser needs a reasonable understanding of your financial situation, risk tolerance, investment experience, and goals. Most enforcement problems start here. An adviser who pushes high-commission products into a retiree’s conservative account has failed the duty of care regardless of how the investment performs. The obligation is enough due diligence that every recommendation rests on the client’s actual circumstances, not on the adviser’s incentives.

Best Execution

When the adviser chooses the broker-dealers who execute your trades, the adviser must seek the most favorable total cost or proceeds under the circumstances. That evaluation is broader than commission rates. The SEC has indicated that execution capability, the value of research the broker provides, the broker’s financial responsibility, and responsiveness all factor in.⁴ An adviser who routes trades to a particular broker because the broker gives the adviser perks, rather than because the broker delivers good execution for clients, has a problem.

Ongoing Monitoring

The duty of care does not end at the recommendation. The SEC requires advice and monitoring at a frequency that serves the client’s best interest given the scope of the agreed relationship.³ For a discretionary managed account, that likely means regular portfolio reviews and adjustments as your circumstances change. For a client who hired an adviser for a one-time financial plan, monitoring is narrower. Either way, setting up a portfolio and walking away violates the duty when the agreement contemplates an ongoing relationship.

What the Duty of Loyalty Requires

The duty of loyalty is conceptually simpler and harder to comply with: the adviser must not place its own interests ahead of yours. Every recommendation has to be motivated by your financial success, not the adviser’s compensation structure. The 2019 interpretation states that an adviser must make full and fair disclosure of all material facts relating to the advisory relationship and must eliminate or at least expose all conflicts of interest that might incline the adviser to give advice that is not disinterested.³

A conflict is material if a reasonable client would consider it important when deciding whether to follow the recommendation. Disclosure must be specific enough for the client to give informed consent. Burying a conflict in fine print, or disclosing it in vague language a typical client would not understand, does not satisfy the standard. And disclosure is not a shield against acting against the client’s interest afterward.

Principal Trades Get Special Treatment

One of the most conflict-laden situations is when the adviser wants to buy a security from you or sell one to you out of the adviser’s own account. Section 206(3) prohibits this unless the adviser discloses in writing that it is acting as a principal and obtains the client’s consent before the trade settles.⁵ The SEC treats “completion” as settlement rather than execution, so the adviser can technically execute first and obtain consent before settlement. But the consent must be genuinely informed, with enough detail about the price and commission for you to evaluate the trade, and you must understand you are free to say no.

What You Should See in Writing

The Advisers Act and SEC rules create a layered disclosure system built around two documents.

Form ADV Part 2A

Every registered adviser must deliver its current Form ADV Part 2A brochure to a client before or at the time the advisory contract is signed.⁶ The brochure describes how the firm is compensated, what services it provides, and any affiliations or arrangements that could create bias. If the firm uses client commission credits to pay for research (soft dollars), the brochure must explain that. Firms charging a percentage of assets under management or performance-based fees must spell those structures out.⁷

The brochure is not a one-time delivery. When material changes occur, the adviser must send an updated brochure or a summary of changes within 120 days of the end of its fiscal year.⁶

Form CRS

Since 2020, advisers have also had to give retail investors a concise relationship summary called Form CRS (Form ADV Part 3). It cannot exceed two pages in paper format and must be written in plain English. It covers five topics: the firm’s registration status, the services offered and how investments are monitored, fees and conflicts of interest, disciplinary history, and suggested questions to ask.⁸ The form must include a specific statement that the adviser has to act in your best interest and cannot put its own interest ahead of yours, along with examples of the conflicts that exist.

How This Differs From a Broker’s Best Interest Standard

Investors sometimes hear “best interest” and assume it means the same thing as a fiduciary duty. It does not. Regulation Best Interest (Reg BI), which took effect in 2020, applies to broker-dealers making recommendations to retail customers. Reg BI requires the broker-dealer to act in the customer’s best interest and not place its own interest ahead of the customer’s, but it is tailored for transaction-based relationships and does not impose an ongoing monitoring obligation.⁹

The Advisers Act fiduciary duty applies to the entire advisory relationship for as long as it lasts. An investment adviser must provide ongoing advice and monitoring appropriate to the scope of the agreement, manage conflicts continuously, and cannot satisfy the duty through one-time disclosures. Neither standard requires the professional to recommend the single cheapest or highest-performing product; both use a principles-based evaluation of whether the professional acted in the client’s best interest given all the circumstances.⁹ The practical difference is that an adviser’s obligation is broader, more continuous, and harder to satisfy with a checkbox approach.

What Happens When an Adviser Breaches the Duty

The SEC has a broad set of tools for advisers who breach their fiduciary duty. On the civil side, the Commission can seek injunctions, disgorgement requiring the adviser to return profits earned from the violation, and monetary penalties. It can also impose industry bars that permanently remove an individual from the advisory business.¹⁰ Disgorgement is particularly consequential because the SEC can direct those funds back to harmed investors.

Criminal exposure is separate. Any person who willfully violates the Advisers Act or an SEC rule under it faces up to five years in prison and a fine of up to $10,000 upon conviction.¹¹ Criminal cases in practice tend to involve deliberate fraud rather than negligent compliance failures, but the authority reaches any willful violation.

Clients themselves have recourse. Section 215 provides that any contract made in violation of the Advisers Act is void as to the rights of the person who committed the violation.¹² Courts have also recognized an implied private right of action under Section 206, allowing clients to sue advisers directly for breaches of fiduciary duty, though the scope of available remedies varies.

When the Duty Attaches and How Long It Lasts

The duty’s practical reach depends on what the adviser and client agreed to. An adviser managing your entire portfolio under full discretionary authority faces the highest level of scrutiny, because every trade made without prior client approval must independently satisfy both the duty of care and the duty of loyalty. An adviser hired to produce a financial plan covering only retirement accounts has a narrower scope, but the fiduciary standard applies fully within it.³

The relationship typically begins when the client receives the adviser’s disclosure documents and signs the advisory agreement. Termination usually requires written notice as specified in the contract. Once the contract ends, the adviser’s proactive duty to monitor your account and provide new advice ceases. The obligation to maintain confidentiality over your financial information, however, survives termination. Advisers who retain discretionary authority during a notice period remain fully bound by the fiduciary standard until authority is formally revoked.

1
Office of the Law Revision Counsel. 15 U.S. Code 80b-6 – Prohibited Transactions by Investment Advisers
2
U.S. Securities and Exchange Commission. Securities and Exchange Commission v. Capital Gains Research Bureau, Inc.
3
U.S. Securities and Exchange Commission. Commission Interpretation Regarding Standard of Conduct for Investment Advisers
4
U.S. Securities and Exchange Commission. OCIE Risk Alert – Investment Adviser Best Execution
5
U.S. Securities and Exchange Commission. Interpretation of Section 206(3) of the Investment Advisers Act of 1940
6
eCFR. 17 CFR 275.204-3 – Delivery of Brochures and Brochure Supplements
7
U.S. Securities and Exchange Commission. Form ADV Part 2 – Uniform Requirements for the Investment Adviser Brochure and Brochure Supplements
8
U.S. Securities and Exchange Commission. Form CRS Relationship Summary (Form ADV, Part 3)
9
U.S. Securities and Exchange Commission. Regulation Best Interest and the Investment Adviser Fiduciary Duty
10
U.S. Securities and Exchange Commission. Remedies and Relief in SEC Enforcement Actions
11
Office of the Law Revision Counsel. 15 U.S. Code 80b-17 – Penalties
12
Office of the Law Revision Counsel. 15 U.S. Code 80b-15 – Validity of Contracts