Undersea cables form the backbone of global communications, carrying over 95 per cent of all international internet traffic. For most people, the internet evokes images of orbiting satellites and transmission towers. In reality, the vast majority of global data flows through physical cables resting on the ocean floor — lines no thicker than a garden hose. These shielded cables transmit terabits of data per second, carrying everything from streaming media and phone calls to financial transactions.
Ownership: Private Corporations and Tech Giants
Surprising as it may seem, the vast majority of undersea cables are owned by private entities. From telecommunications providers to tech conglomerates, the lifelines of global communication belong primarily to a handful of corporations — raising crucial questions regarding power, monopoly, and infrastructure security.
1. Telecommunications Companies and Consortia
Major telecom providers such as Verizon and Orange own extensive shares in submarine networks. To manage high financial burdens and deployment risks, these providers frequently form international consortia to build joint cable systems — such as the SEA-ME-WE (South-East Asia–Middle East–Western Europe) network. While technology giants historically participated in these consortia as junior partners, they have increasingly shifted toward building and owning proprietary cable infrastructure.
Although telecom operators are no longer the sole primary owners, specialized manufacturers remain essential. Companies such as SubCom and Alcatel Submarine Networks lead the manufacturing market, designing multi-layered steel and polymer casings that shield delicate optical fibres from extreme pressure and physical damage.
2. The Rise of Big Tech Infrastructure
Newer cable projects are increasingly owned outright by single technology corporations. Hyperscalers such as Google, Amazon, Microsoft, and Meta dominate this space. Google alone maintains full or partial ownership in numerous major cables — including Grace Hopper (connecting the US and UK), Curie (connecting the US to Chile), and Dunant (connecting the US to France). Similarly, Meta has co-funded massive infrastructure initiatives such as 2Africa, a circum-continental cable encircling Africa to connect 23 countries across three continents.
Governments, National Security, and Geopolitics
While governments rarely own cables directly, state authorities play a critical role in regulating, monitoring, and permitting infrastructure deployment. Because cables cross international waters, state bodies and multilateral agencies coordinate the complex legal frameworks required before underwater installation can begin. Governments also invest in landing rights and domestic infrastructure to secure resilient national connectivity.
Submarine cables have evolved into significant instruments of geopolitical power. Rather than neutral technological utilities, they serve as strategic leverage between competing nations. The rivalry between the United States and China extends directly to subsea communication routes: as Beijing expands its Digital Silk Road initiative across global cable routes, Washington has actively restricted Chinese-based firms from participating in Western-backed cable projects.
Conversely, submarine infrastructure is increasingly deployed as a tool of soft power and diplomacy. The US, Japan, China, and Australia have funded subsea connections for island nations across the Indo-Pacific to address connectivity deficits and deepen diplomatic ties. Australia, despite lacking a state-owned national cable company, actively funds neighboring Pacific island cable networks to foster regional stability and economic integration.
Accidental Damage versus Subsea Sabotage
Despite heavy protective armouring, undersea cables remain vulnerable to physical disruption — frequently caused by ship anchors, commercial fishing trawlers, or seismic activity. Damage to these lines can cause widespread regional outages, triggering immediate economic and operational disruptions.
In late 2024, a series of suspicious cable disruptions in the Baltic Sea raised global security concerns. In November, a subsea link connecting Sweden and Lithuania was severed, alongside a parallel cable linking Finland and Germany, with both incidents linked by maritime authorities to a Chinese bulk carrier.
Weeks later, a shadow vessel monitored by Finnish and Estonian maritime forces damaged an interconnector and four data cables before Finnish authorities detained the vessel as it approached a sixth target. Shortly thereafter, a Maltese-flagged bulk carrier struck another cable connecting Sweden and Latvia. Although Swedish authorities later released the vessel due to insufficient evidence of deliberate intent, the pattern alerted naval strategists globally.
These incidents underscore a shifting paradigm in national defense. Governments increasingly recognize that subsea infrastructure damage cannot automatically be presumed accidental, making hybrid warfare and intentional subsea sabotage major priorities for international maritime defense.