Monopsony: Why Local Labor Markets Have Wage-Setting Power

Monopsony — market power on the buyer side — is the cleanest economic explanation for why minimum-wage increases haven't produced the unemployment the textbook predicts. Recent empirical work shows monopsony effects are widespread, not just in company towns.

Monopsony is the labor-market mirror of monopoly. A monopolist faces a downward-sloping demand curve and can set prices above marginal cost. A monopsonist faces an upward-sloping labor-supply curve and can set wages below the worker's marginal product. The empirical question is how prevalent monopsony actually is in modern labor markets, and the research consensus has shifted substantially in the last decade.

The Classic Monopsony

The textbook example is the company town: a single employer is the only buyer of labor in a given location. The miner cannot easily move elsewhere; the local mining company can pay below the miner's productivity because the alternative is unemployment. The 19th-century Appalachian coal towns are the canonical case, and the framework was treated as a historical curiosity through most of the 20th century.

The textbook treatment in mainstream labor economics through the 1990s was that monopsony was rare and labor markets were approximately competitive. The wage-setting power of any single employer was constrained by workers' ability to move, switch employers, or accept lower hours. The minimum-wage research that found minimal employment effects from minimum-wage increases (Card and Krueger 1994) was re-interpreted by some researchers as evidence that labor markets were closer to monopsony than the competitive framework implied — but this remained a minority view.

The Empirical Reframing

The 2010s produced a wave of papers that established monopsony as much more pervasive than the 1990s consensus assumed. Ioana Marinescu, Suresh Naidu, Alan Manning, and others showed using job-board data that most local labor markets have very few employers — often four or five — for any given occupation. Workers' actual outside options are much narrower than the competitive framework assumed.

The empirical work also showed that workers' wage sensitivity to their employer's wage offer is much lower than the competitive framework requires. If workers were perfectly mobile and informed, they would leave an employer that paid below market — and the employer would face an infinitely elastic labor supply at the market wage. Actual labor-supply elasticities are between 0.3 and 1.5 for most occupations, which is consistent with substantial monopsony power rather than competitive markets.

What Sustains the Power

Several mechanisms keep labor markets less competitive than the textbook assumes:

Geographic friction: most workers do not relocate for incremental wage gains because of family, schooling, and housing costs.
Occupational specialization: workers' skills are often specific to a narrow set of employers in a given area.
Information asymmetries: workers do not know the full set of available offers, and employers know more about their own pay practices than candidates do.
Non-compete agreements: which legally restrict workers from moving to competitors.
No-poach agreements: under which employers tacitly agree not to hire each other's workers, sometimes formalized in franchise contracts.
Visa-tied employment: H-1B and similar work-visa structures lock workers to a specific employer, reducing mobility further.

Each of these mechanisms has been documented in specific industries, and the cumulative effect across an economy is substantial.

The DOJ and FTC Response

The 2010s also produced the first serious antitrust enforcement against labor-market monopsony in decades. Major cases:

Silicon Valley wage-fixing settlements (2014-2015) for Apple, Google, Intel, Adobe, and others agreeing not to recruit each other's engineers.
Restaurant chain no-poach litigation (2017-2020) against fast-food franchise systems with chain-wide no-recruitment policies.
Hospital wage-fixing cases (2010s) in several metropolitan areas.
The 2024 FTC final rule banning most non-compete agreements, currently under litigation.

The enforcement is incomplete and the legal landscape is uncertain — the 2024 FTC non-compete rule will be litigated for years, and the no-poach litigation has produced settlements but not strong precedents. But the framing has shifted: labor-market concentration is now treated as an antitrust concern in mainstream legal-academic and enforcement settings, which it was not a decade ago.

The Minimum-Wage Connection

If labor markets are competitive, a minimum-wage increase above the market clearing wage destroys employment. If they are monopsonistic, a minimum-wage increase up to the worker's productivity can increase both wages and employment, because it reduces the monopsonist's ability to suppress wages below marginal product. The empirical finding that moderate minimum-wage increases have small employment effects is much more consistent with the monopsonistic model than with the competitive one.

This is the strongest practical implication of the monopsony reframing for policy. Minimum-wage increases that would be welfare-destroying in a competitive market are welfare-improving in a monopsonistic one, which substantially changes the cost-benefit calculation for state and local minimum-wage policies.

The Honest Reading

Monopsony is not the explanation for everything, but it is a real and significant feature of US labor markets that the previous generation of labor economics under-counted. The combination of geographic friction, occupational specialization, non-compete agreements, and outright collusion produces wage suppression that would not occur in genuinely competitive markets. The antitrust and regulatory response has begun but is incomplete. The policy implications — for minimum-wage policy, for non-compete restrictions, for antitrust enforcement — are substantial, and the next decade will test whether the framework holds up in court and produces measurable wage gains for affected workers. The intellectual shift in mainstream labor economics has already happened; the institutional shift in enforcement is still in early innings.

The Framework Shift's Implications

The shift from a competitive-labor-market framework to a monopsony framework has policy implications that the mainstream consensus is still working through. Minimum-wage policy looks different. Antitrust enforcement looks different. Non-compete restrictions look different. Visa-tied employment looks different. Each of these areas now has active policy debates that the 1990s consensus would have considered settled. The intellectual shift has already happened in academic labor economics; the institutional shift in policy is still in early innings, and the next decade will determine whether the policy changes follow the academic consensus or whether industry pressure produces another reversal.