Nebius Group said on Wednesday that it plans to raise $4.5 billion by selling convertible bonds. It will use the money to build data centres for artificial intelligence. The Amsterdam-based company set out the plan in a statement.

The offering comes in two parts. Nebius is selling $2.75 billion of notes that mature in 2030, it said. A second series, worth $1.75 billion, matures in 2034. It is selling the bonds privately to large institutional investors. The buyers hold an option to take up to a further $675 million within 13 days of the first issue. That extra allotment splits into $375 million of the 2030 notes and $300 million of the 2034 notes.

Nebius said the money would fund the growth of its business. That covers building and expanding data centres, and developing its AI cloud platform. It also covers buying key components, among them the graphics chips that AI systems run on.

The terms and the market reaction

The bonds are convertible. Holders can swap them for Nebius shares under set conditions, rather than taking repayment only in cash. The 2030 notes carry a coupon of zero to 0.5 percent, according to people familiar with the matter cited by Bloomberg. The 2034 notes carry 4 to 4.5 percent, the same people said. The news agency reported that Nebius expected to price the offering later on Wednesday.

Four banks are running the sale, Bloomberg said, citing the same people: Goldman Sachs, JPMorgan, Citigroup and Bank of America. Spokespeople for Goldman Sachs, Citigroup and Bank of America declined to comment to the news agency. Representatives for Nebius and JPMorgan did not respond to its requests for comment.

The share price moved sharply on the news. Nebius stock fell as much as 9.2 percent in US premarket trading on Wednesday, Bloomberg reported. The drop followed a run of 197 percent this year through Tuesday’s close.

The notes will be senior, unsecured obligations of the company, Nebius said, paying interest twice a year. It cannot redeem either series early before 2028, except in the event of certain tax changes. The company said it could settle any conversions with cash, shares or a mix of the two, at its own choice.

Swapping older debt for shares

Alongside the new bonds, Nebius said it expected to strike separate deals with some holders of its existing convertible notes. Those are its 2 percent notes due 2029 and its 3 percent notes due 2031. Under the deals, holders would exchange part of that older debt for Nebius Class A shares.

The company cautioned that it would negotiate the terms with each holder. Investors taking part might sell the shares or adjust related trades, it said, and those moves could weigh on the share price. It added that the bond sale did not depend on the exchanges going ahead. There was no guarantee any of them would close, it said.

A second big raise in a year

This is the second time in 2026 that Nebius has turned to the convertible market. It raised about $4.3 billion in an enlarged sale earlier in the year, according to Bloomberg. That deal followed a supply agreement with Meta. The company has also borrowed against its GPUs to raise money.

Nebius is one of a group of companies sometimes called neoclouds. It builds and runs data centres, fills them with graphics chips and rents out the computing power to AI and other firms, along with software to run their systems. It has signed multi-billion-dollar supply contracts with Meta and Microsoft, and in May it bought Eigen, a US startup that tunes open-source AI models, for about $643 million in cash and stock, according to Tech.eu.

That model is capital-hungry. The chips are costly, and operators sign long supply contracts that they must build capacity to honour. Nebius has said much of its recent revenue arrived as advance payments from customers, which helps fund the build-out but also commits it to delivering. The convertible market has become a common way for such firms to raise large sums while offering investors a low cash coupon, in exchange for the chance to convert into stock later.

The company trades on the Nasdaq under the ticker NBIS, and founder Arkady Volozh runs it. It has been growing quickly. It reported that its revenue rose sharply in the second quarter, most of it paid in advance by customers. It has also signed capacity deals such as a $1 billion agreement with the AI startup Reflection.

Financing the build-out

The raise is part of a wider scramble to fund the data centres that AI depends on. Building and filling them with chips is expensive, and companies are reaching for debt, share sales and other structures to pay for it. In Europe, firms are racing to secure compute capacity. In the US, regulators are working out how to treat the financing behind these sites.

Nebius has leaned on several of those routes already. It has raised debt secured against its graphics chips, sold convertible bonds and struck advance-paid capacity deals with AI developers. The new offering adds another $4.5 billion to that stack. Its earlier sale in 2026 raised about $4.3 billion, according to Bloomberg.

Nebius said it would set the interest rate, the conversion terms and other details of the new bonds when the offering prices. It repeated that there was no assurance the sale, or the related exchanges, would close.

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