In 2023, migrant workers from Nepal and Bangladesh claimed they had been trafficked to Malaysia and forced to work making parts for the Dyson manufacturer. In Limbu v Dyson Technology Limited, the Court of Appeal (England and Wales) confirmed that England was a suitable forum for the action on the basis that the claimants had arguable claims in tort and that England was the appropriate forum under the forum non conveniens doctrine, as no more suitable forum was available to them. This represents a significant step in the exercise of jurisdiction over transnational supply chain claims. However, the case highlights a bigger problem: how can the claimants demonstrate what happened inside a Tier 3 factory thousands of miles away, in a supply chain that the brand itself contends it did not control? The law can hear the matter. It can’t see the evidence. Not yet.

In 2025, three major legal developments demonstrate regulators attempting to close this gap, and all three possess the same structural blind spot.

In March 2025, the UK Home Office provided new statutory guidance on ensuring transparency in supply chains under section 54 of the Modern Slavery Act 2015 (MSA). The guidance strengthens expectations for corporate disclosures, proposes a tiered reporting system, and calls for corporations to monitor their supply chains beyond Tier 1 suppliers. The guidance, however, changes the underlying legal obligation; section 54 requires the companies to publish a transparency statement. There is no independent verification mechanism, and the compliance remains self-reported. Meanwhile, in the European Union, the Corporate Sustainability Due Diligence Directive (CSDDD), significantly amended by Directive (EU) 2026/470, requires companies to identify human rights risks throughout their value chains, including to indirect suppliers where “objective, verifiable information” indicates a specific risk. The EU Forced Labour Regulation, which will be implemented in December 2027, takes an additional step, allowing customs authorities to prohibit products manufactured with forced labour from the EU market. Together, these measures comprise the most ambitious regulatory framework for supply chain accountability ever developed. Additionally, they suffer from a shared failure; collectively, they generate duties without creating the investigative instruments necessary to discharge them.

This is where open-source investigation (OSINT) comes in, not as a technological breakthrough, but as a legal necessity.

Open-source investigation leverages publicly available information, shipping and customs records, satellite imagery, corporate registry filings, procurement databases, and social media to map supply chain structures and identify indicators of exploitation invisible to conventional audit methodologies. It is not hypothetical in the case of modern slavery. In 2021, Sheffield Hallam University’s report on Xinjiang cotton demonstrated how customs and shipping data may be used to trace forced labour inputs through various levels of supply chains into the goods of big global companies. This is exactly the sort of “objective, verifiable information” the CSDDD obliges corporations to obtain, but the Directive lacks guidance on how to obtain it.

The legal argument is straightforward: Open-Source Investigation should be recognised as a legitimate investigative methodology in modern slavery enforcement regimes. It could have three approaches. First, for regulators: Open-Source Investigation may be a standard tool for customs and national competent authorities to identify at-risk products and supply chains according to the EU Forced Labour Regulation’s enforcement mechanism. Second, for companies: The amended UK MSA guidance recommends firms to map their supply chains, and Open-Source Investigation provides a scalable, economical way to do this beyond Tier 1. Third, for litigation: Cases such as Limbu v Dyson require claimants to establish what occurred inside distant, informally contracted facilities that brands routinely deny controlling. This is the evidentiary burden that conventional corporate disclosure hardly ever meets. Open-source investigation can address it directly: shipping manifests and customs records can establish a direct and documented commercial relationship between a specific factory and a brand, establishing the brand’s knowledge of that facility beyond credible dispute; satellite imagery can document undisclosed production sites operating outside corporate audit procedures; and corporate registry filings can trace the ownership structures through which liability is deliberately obscured across supply chain tiers. Each of these technologies addresses an issue that the courts in transnational supply chain conflicts are already asking, and that self-reported company compliance data cannot answer.

The UK Joint Committee on Human Rights announced in January 2025 that it will be conducting an inquiry into forced labour in UK supply chains. It published its findings in July 2025. The Committee observed that products manufactured employing forced labour are entering the UK market, that the UK risks becoming a dumping ground for products banned overseas, and that comprehensive supply chain due diligence is urgently needed. However, the report’s proposals still do not answer the central question of a standardised approach. How should businesses, regulators and enforcement agencies actually see through the supply chains they are now legally obligated to scrutinise?

Open-source inquiry is not a supplementary tool waiting to be discovered. It is the investigative system that provides practical enforceability to these duties.