Exhibit 99.1

Operating and Financial Review and Prospects

First Half of the Year 2025 and 2024

You should read the following discussion and analysis of our financial condition and results of operations for the six months ended June 30, 2025 and 2024 in conjunction with our unaudited condensed consolidated financial statements and related notes appearing elsewhere in this Report on Form 6-K, as well as our audited consolidated financial statements and the “Operating and Financial Review and Prospects” section of our 2024 Annual Report on Form 20-F, filed with the Securities and Exchange Commission on April 30, 2025. In addition to historical information, this discussion contains forward-looking statements based on our current expectations that involve risks, uncertainties and assumptions. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of various factors, including those set forth in the “Risk Factors” and “Forward-Looking Statements” sections of our 2024 Annual Report. The historical results described below relate to the results of our continuing operations.

Overview

Nebius Group N.V. (or the “Company”) and its subsidiaries (or “the Group”) are a technology group building full-stack AI infrastructure including high-performance GPU clusters, a proprietary cloud platform, and advanced tools for AI model training and inference to support the rapid growth of the global AI industry. The Group operates two smaller business units, Avride and TripleTen, which are described below. In addition to our smaller business units, we own equity stakes in both Toloka and ClickHouse. Headquartered in Amsterdam and listed on Nasdaq, we have a global footprint with R&D hubs across Europe, North America and Israel.

A detailed description of our business, key trends impacting our results of operations and our recent divestment transaction is contained in the “Operating and Financial Review and Prospects” section of our 2024 Annual Report.

Operating Segments

Our primary business, Nebius, is an AI cloud infrastructure company, delivering high-performance compute solutions that power AI development at scale. Our full-stack approach incorporates data centers, custom-designed hardware, and an intelligent software layer, enabling us to deliver high-performance GPU clusters, a proprietary cloud platform, and advanced tools for AI model training and inference. In addition to our core business, we have two other distinct businesses that operate under separate brands:

Starting the second quarter of 2025, the Company introduced the following changes to the segments under which it previously reported financial results:

Toloka, an AI development platform, previously constituted an operating segment within the Group. In May 2025, following the completion of a third-party investment in Toloka, Nebius ceased to hold majority voting power in Toloka and no longer includes Toloka’s results in Nebius’ consolidated financial statements; the Company now reports its stake as an equity method investment. Comparative financial information appearing elsewhere in this Report on Form 6-K has been recast to reflect the results of Toloka within discontinued operations.

Results of Operations

The following table presents our historical consolidated results of continuing operations for the periods indicated:

Net income from continuing operations was $398.2 million in the first half of 2025, compared with a net loss of $185.5 million in 2024. The net income for the six months ended June 30, 2025, is primarily due to the gain from the revaluation of our investment in ClickHouse. Loss from operations increased from $182.5 million to $231.5 million, reflecting the continuing expansion of our core infrastructure business, partially offset by improved operating margins.

Revenues

The table below presents information about the revenues by the reportable segments:

Eliminations represent the elimination of transactions between the reportable segments, including use of our Nebius cloud platform by other segments within the Group.

Revenues by reportable segment:

Total revenues increased by $131.8 million, or 545%, from $24.2 million in the first half of 2024 to $156.0 million in the first half of 2025. This increase was predominantly driven by the revenues generated by our core AI infrastructure business, Nebius, as well as solid growth in TripleTen.

Revenues for the core Nebius business grew by $117.7 million, from $17.4 million in the first half of 2024 to $135.1 million in the first half of 2025. The growth of the Nebius business was largely due to the increase in the number of customers and expansion of our ecosystem, facilitated by the extension of our data center facilities and growth in our installed base of GPUs.

Revenues from TripleTen grew by $12.6 million, or 124%, from $10.2 million in the first half of 2024 to $22.8 million in the first half of 2025. The main driver for the growth in TripleTen’s revenues was the strong growth in student enrollment and rising average check.

The Avride business had only a limited contribution to the total revenue for the Group.

Operating Costs and Expenses

We classify operating costs and expenses as follows: cost of revenues; product development; sales, general and administrative expenses; and depreciation and amortization.

Cost of revenues primarily consists of costs of operation and co-location of data center facilities, the electricity, utility and maintenance costs in data centers and other related expenses. The Group’s owned Finland data center together with rented data center facilities are significant components of the Group’s cost of revenues.

The following table presents the cost of revenues in absolute terms and as a percentage of revenues and total operating expenses for the periods presented:

Cost of revenues increased by $42.1 million, or 331%, from $12.7 million in the first half of 2024 to $54.8 million in the first half of 2025. The increase year over year was due to the expansion of our core AI infrastructure business, mainly driven by costs incurred for co-location and operating lease agreements, as well as the hiring of additional personnel attributable primarily to data-center operations. Our Avride and TripleTen businesses had a limited contribution to the overall increase in cost of revenues.

Product development expenses consist primarily of personnel costs incurred for research and development activities. The following table presents product development expenses in absolute terms and as a percentage of total operating expenses for the periods presented:

Product development expenses increased by $27.8 million, or 54%, from $51.5 million in the first half of 2024 to $79.3 million in the first half of 2025. These increases were primarily due to increases in headcount of personnel engaged in product development activities.

Sales, general and administrative expenses include: expenses for personnel engaged in sales and promotion of products to the market, or performing general or administrative functions, including share-based compensation expenses; rental of office space and related utilities in proportion to the number of employees performing these functions; training and hiring expenses; advertising and marketing expenses, including the costs of organizing promotions; legal and audit services; and other expenses related to the Group’s wider operating activities.

The following table presents sales, general and administrative expenses in absolute terms and as a percentage of total operating expenses for the periods presented:

Sales, general and administrative expenses increased by $6.9 million, or 6%, from $122.2 million in the first half of 2024 to $129.1 million in the first half of 2025. This increase is primarily due to an increase in share-based compensation expense allocated to personnel engaged in sales, general and administrative activities, followed by the growth in marketing and advertising expenses. The growth in these two expense categories was offset by a decrease in consulting, legal and professional fees incurred, which included expenses in the second quarter of 2024 that were incremental to our main operating activities and related to the divestment we completed in that period.

Depreciation and amortization. Depreciation and amortization expense relates to the depreciation of property and equipment, mainly servers and networking equipment, data center equipment and office furniture, and the amortization of intangible assets.

Depreciation and amortization expense increased by $104.0 million, or 512%, from $20.3 million in the first half of 2024 to $124.3 million in the first half of 2025. The growth was primarily due to the increase of depreciation expense related to server and network equipment and infrastructure systems, primarily as a result of the expansion of data center and GPU capacity in our core business, Nebius.

Share-based compensation. In the consolidated statements of operations, share-based compensation expense is recorded in the same functional area as the expense for the recipient’s cash compensation. As a result, share-based compensation expense is allocated among the cost of revenues; product development expenses; and sales, general and administrative expenses.

The following table presents aggregate share-based compensation expense in absolute terms and as a percentage of operating expenses for the periods presented:

Share-based compensation expense increased by $25.0 million, or 353%, from $7.1 million in the first half of 2024 to $32.1 million in the first half of 2025. The growth was due to the awards of RSUs granted under the Company’s equity incentive program in the second half of 2024, following a period of more than two years during which no grants had been made. Grants of share options to the Group’s senior management, including non-executive directors, were the second largest contributor to the growth.

Adjusted EBITDA loss by reportable segments

Our management uses Adjusted EBITDA loss as a financial measure of the performance of our businesses. Adjusted EBITDA loss means U.S. GAAP net income/(loss) from continuing operations plus (1) depreciation and amortization, (2) certain SBC expense, (3) interest expense, (4) income tax expense/(benefit), (5) one-off restructuring and other expenses, less (1) interest income, (2) other income/(loss), net, (3) income/(loss) from equity method investments and (4) gain from revaluation of equity securities. For a reconciliation between total Adjusted EBITDA loss and net loss before income tax expense see Note 14 — “Information about segments & geographic areas” of our condensed consolidated financial statements included elsewhere in this Report on Form 6-K.

The table below presents information about the Adjusted EBITDA loss of the reportable segments:

Adjusted EBITDA loss by reportable segments:

Total Adjusted EBITDA loss for the Group improved by $41.8 million in the first half of 2025 compared to the same period of 2024 primarily due to the increase in revenue, partially offset by growth in cost of revenues, represented by direct costs of our data center facilities, as well as an increase in sales, general and administrative expenses.

Adjusted EBITDA loss for the Nebius business improved by $50.6 million in the first half of 2025 compared to the same period of 2024. As our core infrastructure business continues to scale, we are seeing improving Adjusted EBITDA margin. The Nebius operating segment generated positive adjusted EBITDA in the second quarter of 2025.

Adjusted EBITDA loss of Avride remained stable in the first half of 2025.

Adjusted EBITDA loss of TripleTen increased by $9.0 million in the first half of 2025 compared to the same period of 2024, due to targeted investments into the expansion of its client base in the form of increased marketing expenses and other related student acquisition costs.

Interest Income

Interest income is mainly generated from short-term bank deposits and cash account balances. Interest income remained relatively stable at $12.1 million in the first half of 2025, compared with $13.1 million in the first half of 2024.

Interest Expense

Interest expense of $4.8 million in the first half of 2025 is fully attributable to convertible notes issued by the Company in June 2025.

See Note 12 — “Convertible debt” of our condensed consolidated financial statements included elsewhere in this Report on Form 6-K.

Gain from revaluation of investment in equity securities

Gain from revaluation of investment in equity securities in the amount of $597.4 million in the first half of 2025 represents a revaluation gain of our investment in ClickHouse. based on observable price changes following a third-party investment in ClickHouse during the period.

See Note 5 — “Investments in equity securities and equity method investments” of our condensed consolidated financial statements included elsewhere in this Report on Form 6-K.

Loss from equity method investments

Loss from equity method investments in the amount of $6.2 million in the first half of 2025 primarily reflects a loss related to our remaining stake in Toloka, which was deconsolidated in the second quarter of 2025 and subsequently accounted for under the equity method, offset by income received in the form of cash distributions from our minor stakes in venture capital funds.

See Note 5 — “Investments in equity securities and equity method investments” of our condensed consolidated financial statements included elsewhere in this Report on Form 6-K.

Other Income/(Loss), net

The following table presents the components of other income / (loss), net in absolute terms for the periods presented:

Other income/(loss), net includes foreign exchange losses in the amount of $13.9 million for the six months ended June 30, 2024, and foreign exchange gain in the amount of $10.8 million for the six months ended June 30, 2025.

The functional currency of Nebius Group N.V. is the United States Dollar, which is also the Group’s current reporting currency. Foreign exchange gain/(loss) dynamics reflect changes in the U.S. dollar value of the Group’s monetary assets and liabilities that are denominated in other currencies (primarily the euro), as well as changes in the functional currencies of foreign subsidiaries' monetary assets and liabilities that are denominated in currencies different from their respective local currencies.

Liquidity and Capital Resources

The Group’s principal source of liquidity to date is cash received as partial consideration for the divestment completed in 2024, as well as the proceeds of an equity financing completed in December 2024 and convertible note financing completed in June 2025.

As of June 30, 2025, $1,679.3 million was recorded in cash and cash equivalents. Cash equivalents mainly consist of bank deposits with original maturities of three months or less and investments in money market funds.

The Group’s main cash outflows are as follows: acquisitions of server and infrastructure equipment, investments in construction of new capacities in our proprietary data center in Finland, as well as build-to-suit facilities, lease payments for co-location agreements and other general corporate activities. Our businesses expect to fund their operations, to the extent required, through debt or equity financing, as well as achieving positive operating cash flow in the near- to medium-term.

Cash Flows

Set out below is a summary of cash flows from continuing operations for the six months ended June 30, 2024 and 2025.

Cash flows used in operating activities

Net cash used in operating activities increased by $190.0 million in the first half of 2025 compared to the same period of 2024. The increase mainly resulted from changes in working capital, on the back of improved operating margins of our core business. Changes in operating assets and liabilities resulted in an outflow of $325.6 million in the first half of 2025 and $23.1 million in the first half of 2024, primarily due to changes in VAT reclaimable, other assets, accounts payable and accounts receivable.

Cash flows (used in)/provided by investing activities

Net cash used in investing activities in the first half of 2025 amounts to $1,146.2 and consists primarily of the purchases of property, plant and equipment related to our core infrastructure business, as well as consideration paid for equity securities of ClickHouse and Toloka.

Net cash provided by investing activities in the first half of 2024 amounted to $1,075.3 million and consists primarily of the proceeds from the divestment transaction completed in the period, partially offset by purchases of property, plant and equipment, as well as the effect of deconsolidation of the Group’s former subsidiaries.

Cash received for the divestment consists of cash received in the first closing in May 2024 in the amount of $2,458.1 (see Note 3 — “Acquisitions, Disposals and Discontinued Operations” in the Notes to our consolidated financial statements included in our 2024 Annual Report). As a result of the divestment, we deconsolidated $1,174.9 million in cash and cash equivalents related to discontinued operations as of the date of first closing.

The table below presents information about our capital expenditures:

Capital expenditures relate primarily to our investments in GPUs and data center hardware. After the completion of the divestment in July 2024, we substantially increased the pace of our investments in this area to support the growth of our core business.

Cash flows provided by financing activities

Net cash provided by financing activities in the first half of 2025 was $818.5 million. This amount consists of the aggregate gross proceeds from the issuance of convertible notes in the aggregated principal amount of $1,000.0 million, completed in June 2025. Notes were issued in two tranches of $500 million each, maturing in 2029 and 2031, and represent senior unsecured obligations of the Company. Those proceeds were partially offset by the payment of Dutch dividend withholding tax in the amount of EUR 173.7 million ($181.5 million at the exchange rate on the date of payment) in connection with the portion of the consideration for the divested businesses that was received in the form of the Company’s Class A shares.