The global seafood industry is worth hundreds of billions of dollars, and at its heart lies an uncomfortable truth: a significant portion of the fish that lands on dinner tables around the world has been caught illegally. Illegal, unreported, and unregulated (IUU) fishing — the full name for what most people simply call illegal fishing — accounts for an estimated 20% of the global catch, costing the world economy up to $23 billion a year. For anyone who cares about the ocean, that number is staggering. But here is where things get interesting: the best exotic fish exporters, the massive processing conglomerates, and the global seafood brands that dominate supermarket shelves are not just bystanders in this crisis. They are, in many ways, the most powerful force capable of ending it.

It is tempting to think of illegal fishing as a law enforcement problem — something that coast guards and international agencies need to sort out on the high seas. And yes, those institutions matter enormously. But the real leverage lies upstream, in the commercial relationships that govern who buys fish, from whom, and under what conditions. Large seafood companies sit at the centre of those relationships, and if they choose to use that position responsibly, the ripple effects can be profound.

The Scale of the Problem

To understand why corporate action matters, it helps to appreciate just how difficult illegal fishing is to police through traditional means. The ocean covers more than 70% of the Earth's surface. Fishing vessels number in the millions worldwide, many of them small, fast, and operating in remote waters where no satellite or patrol boat can reach them on any given day. In regions like the Western and Central Pacific, the Indian Ocean, and the waters off West Africa, illegal fishing has devastated fish populations that coastal communities have depended on for generations.

The fish caught illegally does not vanish into thin air. It enters global supply chains — mixed in with legally caught product, relabelled, transhipped from one vessel to another on the open sea, and eventually sold to processors, distributors, and retailers who may have no idea where it actually came from. This "laundering" of illegal catch is the beating heart of the problem, and it is where large commercial buyers have the most potential to intervene.

Traceability: Knowing Where Your Fish Came From

The single most transformative thing a large seafood company can do is demand full traceability from its suppliers. This sounds deceptively simple, but in practice, it means building systems capable of tracking a fish from the moment it is pulled from the water to the moment it reaches a consumer's plate.

Some of the world's leading seafood processing companies have already begun this work in earnest. They are investing in digital catch documentation, electronic monitoring systems on vessels, and blockchain-based platforms that create tamper-resistant records of a fish's journey through the supply chain. When a company can verify that every tuna in its supply chain was caught by a licensed vessel, in a licensed area, using gear that does not harm protected species, the space for illegal product to infiltrate shrinks dramatically.

The challenge, of course, is cost. These systems require investment, and smaller suppliers in developing nations often lack the infrastructure to comply. This is where large buyers can play a constructive role not just by demanding compliance but by helping to fund it — providing technical assistance, co-investing in monitoring equipment, and giving suppliers realistic timelines for meeting new standards rather than simply cutting them off if they fall short.

Purchasing Power as a Policy Tool

When a multinational retailer or restaurant chain decides it will no longer buy from suppliers who can't demonstrate legal, sustainable sourcing, it sends a signal that reverberates through the entire supply chain. This is purchasing power used as policy, and it is one of the most effective tools available.

Fresh tuna suppliers in particular operate in a market where this dynamic plays out daily. Tuna is one of the most traded fish commodities on earth, and it is also one of the most heavily targeted by illegal fishing operations. Companies that source large volumes of tuna have the leverage to insist that their suppliers carry catch certificates verified by Regional Fisheries Management Organisations (RFMOs). They can refuse to buy from vessels that appear on IUU blacklists. They can make flag state scrutiny — paying attention to which country's flag a vessel flies and what that country's fishing compliance record looks like — a standard part of their procurement process.

None of this requires government action. It requires commercial will.

The Indian Ocean Challenge

Nowhere is the need for corporate engagement more urgent than in the Indian Ocean, where some of the world's most biologically rich tuna fishing grounds are under serious pressure. The best Indian Ocean tuna — yellowfin and bigeye in particular — commands premium prices in markets across Asia, Europe, and North America, which makes it a prime target for vessels willing to cut corners on licensing and reporting requirements.

The Indian Ocean Tuna Commission (IOTC) has struggled to enforce compliance across its member states, many of which lack the capacity to monitor their own fleets effectively. Into this regulatory gap, large commercial buyers can step with their own oversight mechanisms. By auditing suppliers, requiring catch documentation that goes beyond minimum legal requirements, and sharing information with enforcement agencies when they encounter suspicious activity, seafood companies can effectively function as a private-sector extension of fisheries governance.

This is not a hypothetical. Several major tuna brands have already introduced their own auditing programs in Indian Ocean source fisheries, and the results — while imperfect — show that commercial pressure does change behaviour on the water.

Worker Welfare and the Human Dimension

Illegal fishing rarely travels alone. It tends to cluster with other forms of exploitation — forced labour, debt bondage, dangerous working conditions, and human trafficking. Vessels that operate outside the law on fishing regulations often operate outside the law in other ways too.

For seafood companies committed to cleaning up their supply chains, this means that labour standards and fishing compliance can't be treated as separate issues. The same auditing frameworks that check for catch documentation should also verify that crew members are being paid, that their passports haven't been confiscated, and that they have the ability to leave the vessel when they choose. Companies that do this work find that it is not only the right thing to do — it also makes their supply chains more resilient, because operations built on exploitation are inherently unstable.

Transparency and Consumer Pressure

There is a growing body of evidence that consumers care about where their seafood comes from — and that they are willing to pay a modest premium for products they can trust. Seafood companies that invest in sustainable sourcing and communicate that investment clearly to consumers are building brand equity that has real commercial value.

Labels, certifications like the Marine Stewardship Council (MSC), and QR codes that link back to catch data are all tools in this space. But perhaps more importantly, companies that publish annual sustainability reports and are willing to name and address the specific challenges in their supply chains build a different kind of credibility — one that pure marketing can't manufacture. Consumers and NGOs have become skilled at spotting the difference between genuine commitment and greenwashing, and the reputational risk of the latter is significant.

Industry Collaboration

No single company can solve illegal fishing alone, and some of the most promising work is happening through industry coalitions. Initiatives like the Seafood Business for Ocean Stewardship (SeaBOS) bring together the world's largest seafood companies to share data, align on standards, and jointly advocate for stronger fisheries governance at the international level. When multiple large buyers send the same signal to the market simultaneously, it creates a rising tide that smaller actors can't easily resist.

This kind of pre-competitive collaboration — where companies that compete fiercely for market share nonetheless align on basic standards — represents a maturing of the industry's approach to sustainability. It acknowledges that if illegal fishing degrades fish populations to the point of collapse, nobody wins, regardless of market position.

The Long Game

Reducing illegal fishing won't happen overnight, and no single company, policy, or technology will solve it entirely. But the trajectory of the past decade is encouraging. Satellite monitoring of fishing vessels has improved dramatically. Consumer awareness is growing. Regulatory frameworks in major markets — including the EU's Catch Documentation Scheme and the US Seafood Import Monitoring Program — are raising the bar for what documentation importers must provide.

What is needed now is for large seafood companies to move from passive compliance with these frameworks to active leadership beyond them. The companies that will define the next era of the seafood industry are those that treat supply chain integrity not as a cost to minimise but as a value to build. They are the ones that will look back in twenty years at oceans that are healthier than they found them — and that will have earned the trust of the consumers, communities, and ecosystems that sustain them.

The ocean has given us an extraordinary abundance. Whether that abundance survives for future generations depends, more than we might expect, on decisions being made in corporate boardrooms today.