Big Tech Is Buying the Ocean Floor

AI demand and hyperscaler ownership are driving a $16B+ submarine cable investment wave unseen since 2000

18 May 2026

A quarter-century ago, the world's telecoms firms buried fibre-optic cable beneath the oceans at a furious pace, only to leave much of it dark when the dot-com bubble burst. History does not always repeat itself, but sometimes it rhymes with unusual precision.

More than $16bn has been committed to new submarine cable systems entering service between 2026 and 2029, according to TeleGeography, a research firm. That matches the investment frenzy of 2000 to 2001. What differs this time is the source of demand. Then, the driving force was speculative appetite. Today it is the rather less glamorous business of moving artificial intelligence workloads across oceans.

The shift in who owns the cables is equally striking. A decade ago, Google, Meta, and Amazon leased bandwidth like ordinary customers. Now they consume more than 70% of global subsea capacity and are buying their way to ownership. Meta is constructing a 50,000-kilometre cable ring at an estimated cost of $10bn. Amazon has launched its first independently built transatlantic system, the Fastnet cable, connecting Maryland to Ireland.

Supply, however, has not kept pace with ambition. SubCom, America's only vertically integrated cable manufacturer, reported a $4.7bn backlog in 2024. Only three Western firms build such cables at all. The number of specialist cable-laying ships is fixed in the short term, and ships, unlike software, cannot be conjured into existence by capital alone. The bottleneck is physical, stubborn, and unlikely to ease quickly.

Governments have taken notice. American lawmakers are advancing bipartisan legislation to impose sanctions for cable sabotage, a threat long regarded as theoretical that is now treated as operational. Europe's CEF Digital programme has committed €347m to protecting and expanding its subsea network.

The deeper issue is one of dependency. Every AI data centre, however vast, ultimately depends on cables it cannot replace to reach users on the other side of the world. That dependency has made subsea infrastructure a strategic asset. Whether the firms now racing to own it have learned the lessons of the last boom remains, as ever, an open question.