Nebius Asked the Bond Market for $4.5 Billion and Priced $5 Billion. No Board Seat Changed Hands.

On Wednesday, Aug. 19, Nebius Group told the bond market it wanted $4.5 billion. Before the day was out, it had priced $5.0 billion. The Amsterdam-headquartered, Nasdaq-listed AI cloud company had pulled off something no venture-backed startup came close to that week: it absorbed roughly half of every dollar that flowed into AI and adjacent companies over a seven-day stretch, without surrendering a board seat, setting a private valuation, or handing an investor a liquidation preference.

The week of Aug. 17 to Aug. 23 saw 60 AI and adjacent rounds announced worldwide, totalling about $11 billion in disclosed capital, according to a StartupHub.ai roundup published Aug. 24. AI infrastructure accounted for five of those rounds and $5.5 billion, almost exactly half the week's total. Nebius alone, logged at its originally announced $4.5 billion size, was about 41 percent of everything raised. For scale: every Series C round announced that week, across every sector, summed to $1.42 billion. Seed and pre-seed together came to $247 million.

The rest of the leaderboard tells the same story. Domyn, the Italian model maker, took $1.1 billion in debt and structured finance; Castelion closed a $1.0 billion Series C led by Andreessen Horowitz and Carlyle; chip startups Etched and Fractile took $700 million and $600 million. Four of the week's top five deals were bets on compute.

The Structure Is the Story

Nebius did not raise venture capital. It issued convertible senior notes in a Rule 144A private placement to institutional buyers, in two series: $3.0 billion of 0.50 percent notes due February 2030, and $2.0 billion of 4.50 percent notes due February 2034. Initial purchasers hold an option for up to $750 million more. Net proceeds are estimated at approximately $4.94 billion, rising to about $5.68 billion if that option is fully exercised. The notes settled Aug. 24.

The conversion terms show how much leverage the company had. The 2030 notes convert at roughly $313.46 per Class A share and the 2034 notes at about $324.65, premiums of 40 and 45 percent to the $223.90 close on Aug. 19. Both carry an accretion schedule that lifts principal to 110 and 125 percent of face at maturity, pushing effective conversion prices to about $344.81 and $405.82, or effective premiums of 54 and 81.3 percent. Nebius is selling equity to bondholders at prices its stock has never traded at, in exchange for paying 50 basis points on the front tranche. It also exchanged $800 million of existing notes for about 15.8 million Class A shares. Proceeds go to data centers, AI cloud development and GPU procurement.

A Business That Grew Into Its Balance Sheet

The financing arrived a week after a quarter that made the ask legible. Group revenue hit $582.3 million in Q2 2026, up 454 percent year over year. AI cloud revenue, roughly 98 percent of the total, grew 514 percent to $574.9 million. Annualized run-rate revenue reached $3.0 billion, up from $1.9 billion in March, and the AI cloud segment posted a 49.7 percent adjusted EBITDA margin.

Founder and CEO Arkady Volozh, who built Nebius out of the 2022 restructuring of Yandex's non-Russian assets and listed it in New York in 2024, called it an inflection. "We closed our largest AI Cloud deals on our strongest terms to date, at prices that represent a step-change in the economics of our business," he wrote to shareholders on Aug. 12. Four deals averaged more than $1 billion in contract value each, and payback on Q2 deals fell to one year and 10 months from a historical two-to-three-year range.

Demand, by his account, now exceeds what the company will sell. "We could sell our entire 2027 capacity on these terms today," Volozh wrote. "We are deliberately not doing so because we see higher value in retaining some capacity for immediate customer needs."

Behind that confidence is an anchor-tenant book most infrastructure companies would envy: a Microsoft agreement worth up to $19.4 billion over five years, and a March 2026 Meta expansion worth up to roughly $27 billion. "We are pleased to expand our significant partnership with Meta as part of securing more large, long-term capacity contracts," Volozh said at the time. "We will continue to deliver."

Why It Matters

The headline number obscures a shift in who is financing the AI buildout. Nebius spent roughly $5.7 billion on capital expenditures in Q2 alone and guides to $20 billion to $25 billion for the year, against revenue guidance of $3.0 billion to $3.4 billion. No venture fund writes that check. So Nebius assembled a stack instead: about $2.8 billion from an at-the-market equity program, a $775 million secured facility in July priced at SOFR plus 250 basis points, more than $9 billion in expected customer prepayments, and now $5 billion in converts.

That is a capital-markets operation, not a venture round. When a weekly funding tracker logs $4.5 billion of it as the largest round of the week, the category is straining. So AI infrastructure has effectively graduated out of venture capital, while applications, agents and tooling compete for a shrinking remainder. Seed and pre-seed founders split $247 million that week. One Dutch bond issue took twenty times that.

The counterweight is duration risk. Nebius carries more than $40 billion in customer commitments and targets 5 gigawatts of contracted power by year end, but the accretion schedules mean it owes more than it borrowed if the equity never gets there.

What to Watch

Watch whether the initial purchasers exercise the $750 million option. Watch whether the short-duration pricing experiment holds: Volozh flagged a $40 million to $50 million per megawatt opportunity against a 2026 base near $12 million, but that premium could compress as Vera Rubin capacity floods the market in 2027. And watch whether the rest of the AI stack can still raise. If infrastructure keeps taking half of every weekly total while contributing a fraction of the deal count, the venture market's center of gravity has already moved to the bond desk.