Antitrust law faces a crisis of complexity. Designed originally as a straightforward mechanism to maintain competition, it has devolved into a realm dominated by economic modeling, arbitrary market definitions, and prolonged litigation and merger reviews. By the time courts render a final judgment, the underlying technology has advanced, the market has shifted, and the world has moved on. The transition to objective decisions informed by economics has instead been marked by subjective decisions to side with one expert over another.

　　The transformation of antitrust law into an endless and expensive battle of experts is largely attributable to the widespread application of the so-called “rule of reason,” which has undermined the law’s effectiveness. Per the Supreme Court’s decision in Continental T. V., Inc. v. GTE Sylvania Inc., application of the rule of reason requires that “the factfinder weighs all of the circumstances of a case in deciding whether a restrictive practice should be prohibited as imposing an unreasonable restraint on competition.” Factfinders have mightily struggled to complete that task. As Professor Jesse Markham Jr. notes, “The rule of reason is no rule at all, but rather a set of vague and inconsistent objectives that a court should set for itself in evaluating conduct under an antitrust challenge.” Unfortunately, the Supreme Court has accelerated a move away from per se rules to the rule of reason, while generally leaving lower courts in the dark as to how to apply this more intensive, extremely subjective analysis.

　　The rule of reason’s insistence on exhaustive inquiries into market effects and potential justifications for anticompetitive behavior has made antitrust cases more expensive, less predictable, and far more time-consuming than necessary. Meanwhile, the core principles of antitrust—promoting competition and protecting economic freedom—have been obscured by technocratic debates that offer little benefit to consumers or markets.

　　Legal scholars and practitioners have long called for a return to simplicity in antitrust law, emphasizing the utility of per se rules in fostering predictability and efficiency. Recent cases such as the Federal Trade Commission’s failed challenge to Microsoft’s acquisition of Activision Blizzard and the Department of Justice’s lawsuit against Visa underscore the urgent need for reform. These cases reveal the shortcomings of an overly complex structure that wastes resources and fails to address genuinely harmful behavior. A simpler, more enforceable antitrust framework would not only promote innovation by reducing uncertainty for businesses but also make enforcement more effective.

　　The Rule of Reason: A Flawed Approach

　　The rule of reason dominates modern antitrust enforcement under Section 1 of the Sherman Act. In the absence of per se violations, it requires courts to conduct a fact-intensive analysis to determine whether a particular practice unreasonably restrains trade. This analysis typically involves examining market structure, competitive effects, and potential pro-competitive justifications, all with a heavy reliance on expert testimony. That said, what the analysis must include remains subject to debate. Markham explains, “Many of the most basic questions about the rule of reason remain needlessly unanswered.” He contends that “after 100 years the courts have not even gone so far to establish whether market power is a necessary element of a rule of reason case and in fact have articulated inconsistent answers to that basic question.” While the rule of reason is intended to distinguish harmful practices from benign or beneficial ones, it has created significant challenges in practice.

　　Instead of fostering competition, the rule of reason often has the opposite effect, deterring entry and innovation while allowing incumbents to exploit procedural complexities to their advantage.

　　The most glaring flaw of the rule of reason is its inefficiency. Antitrust cases governed by this standard often devolve into prolonged disputes over technical economic details, such as market definitions and consumer welfare impacts. Professor Maurice Stucke, for one, has criticized the rule of reason for its reliance on economic models that are both costly and prone to manipulation. In many cases, courts must rely on conflicting testimony from economists, making it difficult to reach a definitive conclusion. This reliance on technical expertise not only delays enforcement but also skews the playing field in favor of well-funded corporations that can afford to hire teams of experts and engage in protracted litigation.

　　The rule of reason may even violate the rule of law. “Under the rule of law, enforcement authorities apply clear legal prohibitions to particular facts with sufficient transparency, uniformity, and predictability, so that private actors can reasonably anticipate what actions would be prosecuted,” Stucke writes. In contrast, decades of application of the rule of reason show that the doctrine lacks those attributes. Citing various court precedents, Stucke observes that the rule of reason “involves a flexible factual inquiry into a restraints overall competitive effect, and the facts peculiar to the business, the history of the restraint, and the reasons why it was imposed.” What’s more, the rule of reason also varies in focus and detail depending on the nature of the agreement and market circumstances.”

　　It should be no surprise that the rule of reason analysis also varies from one judge to another, with predictable inconsistency.

　　Flaws with the rule of reason do not end there. The rule of reason introduces substantial uncertainty for businesses. Because the outcome of a case often hinges on the aforementioned variable, nuanced, and case-specific factors, firms cannot reliably predict whether their practices will be deemed lawful. This uncertainty discourages legitimate competitive behavior, particularly in innovative industries where firms must take risks to succeed. Instead of fostering competition, the rule of reason often has the opposite effect, deterring entry and innovation while allowing incumbents to exploit procedural complexities to their advantage. And the bigger the incumbent, the bigger their advantage in such an arbitrary system.

　　The Value of Per Se Rules

　　Per se rules offer a clear and enforceable alternative to the rule of reason. These rules categorically prohibit certain practices, such as price-fixing, bid-rigging, and market allocation, without requiring detailed analysis of their competitive effects. By eliminating the need for lengthy economic inquiries, per se rules streamline antitrust enforcement and provide much-needed predictability for businesses.

　　Legal scholars such as William E. Kovacic have argued that per se rules can streamline prosecution of behaviors with no plausible pro-competitive justifications. The predictability provided by per se rules benefits both regulators and businesses by reducing litigation costs and encouraging compliance. When firms know that specific practices are unequivocally prohibited, they can structure their behavior accordingly, fostering a more competitive and dynamic marketplace. The guessing game introduced by antitrust enforcers who prioritize vibes over the rule of law spells disaster for upstarts and unicorns, corner stores and megastores.

　　Expanding the use of per se rules would address several of the key shortcomings of the current antitrust framework. First, it would reduce the costs and delays associated with litigation, allowing regulators to focus their resources on identifying and addressing harmful conduct. Second, it would level the playing field by removing the advantage that well-funded corporations currently enjoy under the rule of reason. Finally, it would provide greater clarity and certainty for businesses, encouraging innovation and competition by reducing the risks associated with compliance.

　　Misguided Enforcement and the Costs of Complexity

　　Recent antitrust cases highlight the inefficiencies and missed opportunities caused by the current reliance on the rule of reason. The FTC’s failed challenge to Microsoft’s acquisition of Activision Blizzard provides a clear example. The FTC argued that the merger would harm competition in the gaming industry by enabling Microsoft to withhold popular games from competitors. As noted in ProMarket as well as by federal district court judges, however, the agency’s case relied on speculative theories of harm that lacked empirical support. The court ultimately rejected these arguments, pointing out that they failed to account for the dynamic and competitive nature of the gaming industry. But these sorts of unmoored arguments are only possible in a needlessly complex antitrust regime—reform is necessary.

　　The Department of Justice’s lawsuit against Visa similarly illustrates the pitfalls of an overly complex approach to antitrust enforcement. The case focuses on Visa’s alleged dominance in the debit card market, despite substantial evidence that this market remains highly competitive. Consumers have access to numerous payment alternatives, including Apple Pay, Google Pay, and Venmo, and new entrants continue to innovate in the space. Critics, including Jack Soloway of the Cato Institute, have argued that the DOJ’s narrow focus on Visa’s market share ignores broader systemic issues, such as regulatory barriers that hinder competition.

　　These cases reveal a troubling pattern: antitrust enforcement that prioritizes speculative economic modeling and narrow market definitions over practical and timely intervention. By focusing on a rotating set of amorphous factors rather than clear evidence of anticompetitive behavior, regulators waste resources and fail to address the root causes of market distortions.

　　The costs of antitrust complexity extend beyond enforcement inefficiencies to the broader economy. Businesses, particularly startups and smaller firms, often lack the resources to navigate the legal and economic challenges posed by the rule of reason. This dynamic is especially harmful in innovative industries, where firms must make bold investments and take risks to compete.

　　The uncertainty created by complex antitrust rules further compounds this problem, deterring entrepreneurs from entering competitive markets and discouraging established firms from pursuing innovative business models.

　　Simplifying antitrust law by expanding per se rules would address these challenges by providing greater clarity and predictability. Furthermore, the feared treble damages should be limited to per se antitrust violations, thereby meaningfully prioritizing enforcement against per se violations vis-à-vis much more speculative and economically harmful litigation conducted under the rule of reason.Entrepreneurs would be free to innovate with less fear of inadvertently violating unclear or unpredictable regulations, while regulators could focus their efforts on addressing genuinely harmful conduct.

　　Lessons from Antitrust’s Founders

　　The architects of antitrust law recognized the importance of simplicity and enforceability. The Sherman Act, passed in 1890, was designed to address clear and identifiable restraints on trade, such as collusion and monopolization, without relying on complex economic theories. Regression analysis wasn’t a thing in the late nineteenth century. That’s why the drafters of the Sherman Act trusted courts to apply common sense and straightforward principles, rather than engaging in lengthy and technical analyses.

　　Justice Louis Brandeis, a staunch advocate for decentralized competition, emphasized that antitrust law’s effectiveness depends on its ability to provide clear guidance and swift enforcement. Brandeis understood that excessive concentration of economic power stifles opportunity and innovation, a lesson that remains relevant today. The roots of liberty as a principle of antitrust law extend even further back. The “natural liberty of mankind” espoused by Sir William Blackstone was top of mind for the American Founders. Like Blackstone, they believed that men should have the “power of choosing those measures [to pursue happiness] which appear to him to be most desirable.” That view worked its way into several state constitutions, which explicitly banned monopolies as tyrannical entities.

　　Blackstone’s legal philosophy further demonstrates the value of simplicity, emphasizing that laws should be accessible and understandable to the public. Modern antitrust law, with its reliance on technical expertise and economic modeling, has strayed far from these principles, creating a system that benefits large corporations at the expense of consumers and smaller competitors.

　　Balancing Simplicity and Flexibility

　　Critics of per se rules often argue that they sacrifice flexibility and risk penalizing legitimate business practices. While these concerns are valid, they are outweighed by the benefits of simplicity and enforceability. Per se rules can be carefully tailored to address practices that are unequivocally harmful, such as price-fixing, bid-rigging, and market allocation, while leaving room for a more flexible approach in cases where the competitive effects are genuinely ambiguous. Even in the latter group of cases, though, antitrust law must not facilitate situations in which established companies can rely on their economic and legal might to bleed upstarts dry through prolonged litigation.

　　A focus on economic dynamism can inform the development of new, easily applicable per se rules in furtherance of broad economic goals. A dynamic economy bears the following attributes: creative destruction in which new firms and innovations can upend entrenched rivals, rapid diffusion of knowledge and innovations, flexible resource allocation, low barriers to entry and exit, and decentralization of power. In such an economy, citizens as consumers and entrepreneurs maintain agency, with more rather than less options and—all other things being equal—lower rather than higher prices.

　　With this guiding framework in mind, Congress should add to the list of per se rules. One place to start is a prohibition on self-preferencing. This practice allows large platforms to manipulate search results to favor their own products over others. Under the consumer welfare approach, assuredly some economists could craft an empirical model that suggests that consumers benefit from self-preferencing. They may show that in some cases consumers experience a net benefit from lower search costs and cheaper products offered by the platform in question.

　　A threshold inquiry into whether such a practice, in theory, would increase economic dynamism returns the opposite result. All else equal, more competition allows for more competitors, more innovation, and more consumer choice at lower prices. This approach would achieve several benefits over the status quo. Application of this rule would force large platforms to compete on price with competitors that the platforms could no longer hide from consumers. What’s more, application of this rule fits more squarely within the capacity of judges (and their clerks), without the necessity of experts.

　　Through striking a balance between simplicity and flexibility, antitrust law can remain effective while reducing the burdens and inefficiencies of the current system.

　　A full list of other per se rules that may achieve similar results is beyond the scope of this essay. But that should not stop Congress from getting to work on enacting a per se rule against self-preferencing and actively studying which additional per se rules should follow. Prolonged inaction on this front will only prolong the ability of established companies to use litigation as a sword and regulators to use ambiguous standards to punish their political enemies.

　　Even with a clearer framework in place to guide congressional study of per se rules, some allegations of anti-competitive behavior will invite and merit further analysis. An additional reform can help prevent these cases from succumbing to regulatory abuses and strategic delays. To avoid such litigation being mired in motions for summary judgment and massive discovery as is the case under the rule-of-reason approach, Congress should direct courts to apply an economic dynamism filter at the outset of litigation. Application of this dynamism filter should minimally include the following procedural requirements:

　　1. Require plaintiffs initial pleadings to specifically identify how challenged conduct impedes one or more defined attributes of market dynamism (creative destruction, knowledge diffusion, resource flexibility, entry/exit, power decentralization) and its effect on consumers, including but not limited to price effects.

　　2. Create a rebuttable presumption of anticompetitive effect if plaintiff demonstrates in their initial pleadings impediments to market dynamism that raise consumer costs (or impede the lowering of such costs), shifting the burden to defendant to show business necessity.

　　3. Limit initial discovery to documents and testimony directly relevant to theoretical market dynamics impact and business justification, deferring extensive empirical analysis unless plaintiff proves market harm and then only if defendant fails to overcome the presumption.

　　Additions and refinements to this list by Congress should occur over time. Any such amendments should align with the substantive ends of reducing the odds of arbitrary enforcement and death of competition by way of litigation. A similar step in patent litigation, Markman hearings, has already demonstrated how procedural innovation can further substantive ends and reduce wasteful litigation. By front-loading claim construction before full discovery, these hearings can create pathways for earlier resolution—whether through settlement or focused litigation—while ensuring that subsequent discovery remains anchored in the courts careful interpretation of patent scope. A similar process may serve similar ends in the antitrust context.

　　Finally, Congress should limit the treble damages remedy to per se violations. Such a change will disincentivize plaintiffs from pursuing spurious cases and from using litigation for strategic advantage, as well as skewing cases toward per se violations—exactly the direction that provides more predictability and efficiency for businesses and innovators.Congress should target its treble damages hammer more surgically to achieve its policy ends.Limiting treble damages strictly to per se violations allows America’s anti-trust laws to be more effective in bringing about both the innovations and dynamism we want, while appropriately reining in clearly anti-competitive behavior.

　　By striking a balance between simplicity and flexibility, antitrust law can remain effective while reducing the burdens and inefficiencies of the current system. Antitrust law has become too complex to effectively fulfill its mission of protecting competition and fostering innovation. The rule of reason, with its reliance on economic modeling and speculative analyses, has made enforcement inefficient, unpredictable, and inaccessible to many. Expanding the use of per se rules offers a practical and enforceable alternative, simplifying antitrust law while preserving its core principles.

　　Recent cases such as the FTC’s failed challenge to the Microsoft-Activision merger and the Justice Department’s lawsuit against Visa illustrate the shortcomings of the current framework. By focusing on technicalities rather than clear evidence of anticompetitive behavior, regulators have squandered resources and missed opportunities to address genuinely harmful conduct. Simplifying antitrust enforcement would promote innovation by reducing uncertainty for businesses and ensuring that bad actors face timely accountability.

　　Antitrust law was never intended to be a tool for bureaucratic overreach or mere academic debate. It was designed to protect competition and ensure that markets remain open and fair. By returning to its original principles and embracing simplicity, antitrust law can once again serve as a powerful tool for promoting innovation and economic growth—in short, economic dynamism. It is time to abandon the complexities that have bogged it down and refocus on what truly matters: safeguarding competition, fostering a dynamic and competitive economy, and promoting individual liberty.