Identify Prohibited Practices — Identify conflicts of interest and prohibited practices (e.g., insider trading, selling away).

The modern framework governing prohibited practices in the securities industry did not emerge in a vacuum; rather, it was forged through decades of financial scandal, market manipulation, and investor harm. Before the 1930s, the U.S. securities markets operated with minimal federal oversight, and practices that we now consider clearly unethical—such as trading on material nonpublic information or churning client accounts—were widespread and often tolerated. The catastrophic 1929 stock market crash and ensuing Great Depression exposed the systemic dangers of unregulated markets, galvanizing Congress to erect the foundational statutory architecture that still governs Wall Street today.

This historical arc reveals the central question that the prohibited practices framework seeks to answer: How can regulators ensure that financial professionals act in their clients' best interests rather than exploiting informational, positional, or relational advantages for personal gain? The answer lies in a detailed taxonomy of forbidden conduct, from insider trading to selling away, each targeting a specific vector of potential abuse.

Prohibited practices under securities law can be organized around several foundational principles. At the highest level, investment advisers, investment adviser representatives (IARs), broker-dealers, and their agents owe duties of loyalty and care to clients. Violations of these duties manifest in specific categories of misconduct that the Uniform Securities Act, the Investment Advisers Act of 1940, and SEC rules expressly prohibit. Understanding these categories requires grasping several core definitions that recur throughout the Series 65 examination.

The diagram above illustrates the three primary vectors through which prohibited practices arise. Information-based violations occur when professionals exploit an asymmetry of knowledge—they know something the market does not. Transaction-based violations center on the mechanics of trading itself, where frequency, authorization, or pricing is manipulated. Relationship-based violations exploit the trust and structural dependencies inherent in the adviser-client or agent-firm relationship. On the Series 65 exam, questions frequently require candidates to classify a given scenario into one of these categories and identify which specific rule or statutory provision has been violated.

Insider Trading — The Mechanics of MNPI

Insider trading liability under SEC Rule 10b-5 requires two elements: possession of material nonpublic information (MNPI) and a duty not to trade on or disclose that information. Information is considered material if a reasonable investor would consider it important in making an investment decision—examples include advance knowledge of earnings results, merger announcements, regulatory actions, or significant changes in management. Information is nonpublic if it has not been disseminated broadly enough for the market to absorb it. The "classical theory" of insider trading holds that corporate insiders (officers, directors, key employees) breach a fiduciary duty to shareholders when they trade on MNPI. The "misappropriation theory," endorsed by the Supreme Court in United States v. O'Hagan (1997), extends liability to outsiders who misappropriate confidential information from their source—such as a lawyer, accountant, or banker who learns of a pending deal through their professional role.

Selling Away — Trading Outside the Firm

Selling away describes the situation in which a registered agent or IAR engages in securities transactions that are not recorded on the books of his or her employing broker-dealer or investment adviser. This practice is particularly dangerous because it circumvents the firm's compliance and supervisory infrastructure—trade reviews, suitability checks, error-and-omission insurance, and customer complaint tracking all depend on the firm knowing about the transaction. Common selling-away scenarios include an agent independently offering private placements, promissory notes, or limited partnership interests to clients without the firm's knowledge or approval. Under the Uniform Securities Act, selling away can result in denial, suspension, or revocation of an agent's registration and may subject the agent to civil or criminal liability.

Churning — Quantitative Indicators

Regulators assess churning using quantitative metrics alongside qualitative analysis. Two commonly cited measures are the turnover ratio and the cost-to-equity ratio. While these metrics do not constitute a bright-line rule, elevated values—particularly a turnover ratio above 6× or a cost-to-equity ratio above 20%—raise strong presumptions of excessive trading.

Front Running — Exploiting Order Flow Knowledge

Front running occurs when an adviser or agent, aware of a pending client order large enough to move the market, executes a personal trade first to profit from the anticipated price change. For example, if an adviser knows that a client is about to place a $5 million buy order for a thinly traded stock—likely pushing the price up—the adviser buys shares in a personal account before entering the client's order, then sells after the price rise. This practice is prohibited under the Investment Advisers Act's general anti-fraud provisions and the Uniform Securities Act. It also violates the duty of best execution owed to clients.

Several additional prohibited practices merit attention for the Series 65 exam. Guaranteeing against loss—promising a client that they will not lose money on an investment—is expressly prohibited because it misrepresents the inherent risk of securities. Similarly, sharing in client profits or losses is generally prohibited unless the sharing arrangement is proportionate to the professional's capital contribution and the client provides written consent. Borrowing from or lending to clients creates obvious conflicts and is prohibited absent very specific conditions (such as when the client is a family member or a financial institution). Lastly, using misleading performance claims—such as cherry-picking favorable periods or failing to net out fees—violates advertising rules and constitutes fraud.

The following scenario is representative of the type of fact pattern you may encounter on the Series 65 exam. Work through it systematically to identify each prohibited practice.

Understanding prohibited practices requires appreciating the different standards of conduct that apply to different types of financial professionals. Investment advisers are held to a fiduciary standard, while broker-dealers have traditionally been held to a suitability standard (now enhanced by Regulation Best Interest). The scope of what constitutes a prohibited practice, and the penalties attached, can differ based on which standard applies.

The prohibited practices tested on the Series 65 represent only the foundation of a broader and continually evolving regulatory landscape. As financial markets become more complex and technology-driven, regulators have extended the principles behind traditional prohibitions to address new forms of misconduct. Understanding these connections helps candidates not only pass the exam but also develop the analytical framework necessary for a career in investment advisory.

Looking forward, the regulatory treatment of prohibited practices will continue to expand. The SEC's proposed climate disclosure rules, evolving ESG investment standards, and the rapid growth of digital assets all present new contexts in which traditional prohibitions—insider trading, conflicts of interest, unauthorized activity—will need to be applied. Candidates who understand the underlying principles rather than merely memorizing lists of violations will be better equipped to navigate this evolving landscape. The Series 65 exam tests your ability to apply these principles to novel fact patterns, not just to recognize keywords.