Rule 10b-18, adopted by the Securities and Exchange Commission on November 17, 1982, established conditions under which a corporation's repurchase of its own shares would be presumed not to constitute illegal stock manipulation. The rule specified four conditions: manner of purchase (through a single broker on any given day), timing (no purchases at the open or during the last half hour of trading), price (not exceeding the highest independent bid or last sale price), and volume (not exceeding twenty-five percent of average daily trading volume). Purchases meeting these conditions received a legal safe harbor—the SEC would presume them lawful and would not bring manipulation charges. This four-page regulatory change transformed American corporate finance. Before 1982, buybacks were rare and legally risky. After 1982, they exploded into a trillion-dollar-per-decade phenomenon. Lazonick identifies Rule 10b-18 as the single most consequential regulatory decision in the history of American corporate governance, because it removed the primary institutional barrier preventing the conversion of corporate earnings into shareholder distributions. In the AI era, the rule operates as the legal infrastructure enabling firms to convert productivity gains into buybacks rather than reinvesting them in the human capabilities that generated those gains.
The SEC's stated rationale for Rule 10b-18 drew on law-and-economics scholarship arguing that buybacks were efficient capital allocation mechanisms unfairly stigmatized by outdated manipulation concerns. The rule's architects believed that liberalizing buybacks would improve market efficiency by enabling firms to adjust their capital structures flexibly in response to investment opportunities. What actually occurred was the systematic diversion of corporate earnings from productive investment to financial distribution. Between 1982 and 2024, aggregate buybacks by U.S. corporations exceeded $10 trillion—resources that were not invested in research, workforce development, or organizational capabilities.
The rule's consequences were not immediate but compounding. In the 1980s, buybacks remained modest relative to dividends. By the 1990s, they had become significant. By the 2000s, they exceeded dividends at many major corporations. By the 2010s, buybacks plus dividends consumed ninety percent or more of net income at S&P 500 companies, leaving negligible resources for productive reinvestment. This trajectory was enabled by the rule's safe harbor, which removed regulatory risk, combined with the stock-based compensation structures that gave executives personal financial incentives to maximize buybacks.
Lazonick has argued consistently for Rule 10b-18's repeal or significant restriction. His position rests on empirical evidence that buybacks function precisely as the pre-1982 regulatory framework assumed they would: as manipulative practices that inflate stock prices for insider benefit at the expense of long-term corporate health and broader economic welfare. The safe harbor's defenders argue that buybacks are voluntary transactions between willing parties and that restricting them would reduce market efficiency. Lazonick's response is institutional: the efficiency argument assumes that stock prices reflect long-term productive value, but when executives can boost prices through buybacks while degrading productive capabilities, the price signal decouples from productive reality. Removing the safe harbor would restore the presumption that buybacks require justification rather than the presumption that they are legitimate.
Rule 10b-18 emerged from SEC deliberations in the late 1970s and early 1980s that reflected the intellectual influence of the law-and-economics movement. Scholars including Daniel Fischel, Frank Easterbrook, and others argued that existing securities regulations were overly restrictive and that market mechanisms could regulate corporate behavior more efficiently than rules. The SEC, responding to these arguments and to corporate lobbying for clarification of buyback legality, adopted a rule intended to provide certainty. The consequences—trillions in distributions, stagnant wages, declining productive investment—were not part of the rule's explicit purpose but were structurally predictable from Lazonick's institutional analysis. Once legal risk was removed and stock-based compensation became dominant, the buyback's function as an extraction mechanism became inevitable.
Safe harbor creates extraction infrastructure. By presuming buybacks lawful rather than requiring justification, the rule shifted the default from restraint to permission—enabling the trillion-dollar distribution explosion.
Interaction with stock-based compensation. The rule's consequences were modest until executive pay became equity-dominated; the combination created personal financial incentives for buyback authorization that overwhelm productive considerations.
Quarterly cycle enabler. Safe-harbor buybacks provide a reliable mechanism for boosting stock prices within the timeframe that matters for quarterly evaluation—making extraction rational on the timescale that governs executive decisions.
Decoupling price from productive value. When stock prices can be increased through buybacks independent of productive performance, the price signal that markets rely on for efficient capital allocation becomes corrupted—misleading investors and misallocating resources.
AI-era intensification. Productivity gains from AI deployment flow directly to earnings available for buybacks, and the safe harbor ensures those buybacks are legally protected—accelerating the conversion of technological capability into shareholder extraction.