In a global economy, capital crosses borders with ease. But antitrust enforcement remains grounded in national jurisdictions, each applying its own rules to markets that no longer fit within their borders. This mismatch creates a dangerous blind spot—one that today’s fragmented competition authorities can’t fix.

Before Meta’s acquisitions of Instagram and WhatsApp, no single Meta platform was considered dominant when assessed in isolation or within a regional framework. However, after the mergers, it came to control the three largest global platforms for messaging and social sharing. As of today, these services collectively reach over 75% of global internet users, based on reported monthly active user counts. While legal in each jurisdiction considered separately, the resulting social media group might raise concerns for a world authority—if one existed.

The issues extend beyond tech. Take the 2016 merger between AB InBev (headquartered in Belgium and the USA) and SABMiller (then based in the UK)—two of the world’s largest brewers. Competition authorities in the U.S. and EU approved the deal after securing regional divestitures. But in many African and Latin American markets—where antitrust institutions are under-resourced, or politically constrained—the merger went largely unchecked.

In Peru, for example, SABMiller already controlled roughly 95% of the beer market, while AB InBev held an additional 4%. After the merger, the combined entity reached nearly 99% market share—a level of concentration that would have likely triggered scrutiny elsewhere. And Peru is not an isolated case. The result was growing dominance in economies that had little ability to assess, let alone challenge, the consolidation. This wasn’t necessarily a failure of law or will, but it highlights the deeper problem: without global coordination, even well-intentioned enforcement in well-regulated jurisdictions can miss the broader competitive consequences.

The issue is a structural misalignment. National regulators assess market power within their own borders. They apply thresholds based on domestic turnover, local user shares, or regional concentration metrics. Each national competition authority lacks legal competence to review mergers whose competitive effects arise exclusively outside the area of jurisdiction. For instance, according to EU law, the Directorate-General for Competition (DG COMP) is empowered to assess only “concentrations which have a Community dimension” (Council Regulation (EC) No 139/2004(9)). In the United States, the Department of Justice and Federal Trade Commission enforce merger control under Section 7 of the Clayton Act (15 U.S.C. §18), which applies only to transactions that may substantially lessen competition within U.S. markets. In Japan, the Fair Trade Commission (JFTC) conducts merger reviews under Article 15 of the Antimonopoly Act and related guidelines, which limit intervention to cases where competition in Japanese markets may be substantially restrained.

But many modern markets—especially in tech, pharmaceuticals, and commodities—are inherently global. In this environment, it’s entirely possible for a firm to acquire dominance bit by bit—each acquisition slipping through national reviews, even as the cumulative effect is to stifle global competition.

When market dominance scales globally, it creates structural barriers to entry that transcend national boundaries. A potential entrant—whether in Nairobi, São Paulo, or Berlin—must now compete not just with local incumbents, but with firms that control global user networks, proprietary data, and entrenched platform ecosystems. The result is a chilling effect on innovation: few startups will risk investing in new products or services when the dominant player can leverage cross-market advantages to outcompete or acquire them early. But the problem is not solely economic—it is also institutional. Cross-border mergers must navigate a patchwork of regulatory systems, each with its own legal thresholds, procedural rules, and enforcement capacities.

The lack of a unified global competition standard creates more than just regulatory gaps—it creates opportunities for strategic manipulation. In theory, a merger that leads to global dominance should raise red flags somewhere. But that assumes every jurisdiction enforces its rules rigorously. In reality, firms can gain dominance by exploiting the weakest links: consolidating power in countries with lax oversight, then staying just below the radar in stricter jurisdictions.

Much like the Basel Committee harmonizes bank capital standards, or the WTO arbitrates trade disputes, a global competition body could improve outcomes by monitoring what no single authority can. Competition policy was introduced as one of the four “Singapore issues” by the WTO in 1996, but was dropped from the agenda again in 2004 — before the rise of tech.

Without a global mechanism to govern competition policy, we’ll continue sleepwalking into monopolies that no one approved, shaped by a regulatory framework built for another era.

Ugo Troiano is an associate professor of economics at the University of California, Riverside. You can follow his Substack:  utroiano.substack.com