ACM Research (Nasdaq: ACMR) closed 2025 with full-year revenue up 15% to $901.3 million - ahead of a roughly flat China WFE market - and fourth-quarter revenue of $244 million, up 9%. Full-year net income attributable to ACM Research was $110.2 million ($1.61 diluted EPS), down from $152.2 million ($2.26) as profitability compressed: Q4 gross margin fell to 41.0% (below the 42%-48% target) and full-year gross margin to 44.5% (from 50.4%), hurt by margin pressure on a few semi-critical products and higher inventory provisions, while full-year operating margin dropped to 15.9% from 25.6% on 34% growth in operating expenses driven by heavy R&D. Full-year shipments fell 12.2% to $854 million against a very strong 2024 (up 63%) and some new-product shipments pushed into 2026. Crucially, 2025 included very little new-product contribution, setting up what management calls a strong 2026 product cycle led by single-wafer SPM cleaning and furnace, with supercritical CO2 dry, panel-level horizontal plating, Track and PECVD building in 2026-2027. ACM announced several landmark wins outside mainland China - a first Singapore foundry cleaning install, Singapore OSAT wafer-level packaging orders, a panel-level vacuum-cleaning tool for a global packaging manufacturer, and North American wafer-level packaging orders - underscoring global expansion, supported by an Oregon U.S. assembly build-out to mitigate tariffs. The balance sheet is strong, with year-end net cash of $845.5 million (up from $259.1 million) including $623 million net from ACM Shanghai's 2025 offering. Management guided 2026 to mid-teens operating margin (similar to 2025), gross margin at the low end of the target range in the first half with a second-half lift, R&D of 16%-18% of sales, and shipment growth outpacing revenue growth, as it invests into a $4 billion long-term revenue opportunity and defends share in China through differentiated, IP-protected technology amid a flood of new local entrants.
Good day, everyone. Thank you for joining us to discuss fourth quarter and fiscal year 2025 results, which we released before the U.S. market opened today. The release is available on our website as well as from Newswire Services. There's also a supplemental slide deck posted to the investor relations section of our website that we will reference during our prepared remarks.
On the call with me today are our CEO, Dr. David Wang, our CFO, Mark McKechnie, and Lisa Feng, our CFO of our operating subsidiary, ACM Shanghai. Before we continue, please turn to slide two. Let me remind you that remarks made during this call may include predictions, estimates, or other information that might be considered forward-looking. These forward-looking statements represent ACM's current judgment for the future. However, they are subject to risks and uncertainties that could cause actual results to differ materially.
Those risks are described under the risk factors and elsewhere in ACM's filings with the Securities and Exchange Commission. Please do not place undue reliance on these forward-looking statements, which reflect ACM's opinions only as of the date of this call. ACM is not obliged to update you on any revisions to these forward-looking statements.
Certain financial results that we provide on this call will be on a non-GAAP basis, which excludes stock-based compensation and unrealized gain or loss on short-term investments. For our GAAP results and reconciliations between GAAP and non-GAAP amounts, you should refer to our earnings release, which is posted on the IR section of our website, and to slides 14 and 15. Also, unless otherwise noted, the following figures refer to the fourth quarter and fiscal year 2025, and comparisons are gonna be with the fourth quarter and fiscal year 2024.
I will now turn the call over to David Wang. David?
Thanks, Steven, hello, everyone, and welcome to ACM's fourth quarter and fiscal year 2025 earnings conference call. I'm pleased with our fourth quarter results, which capped off a solid year of execution. Revenue grew 9% in the fourth quarter and 15% for the full year. We continue to execute well across our core business. We made a lot of progress with new product platforms, we strengthen our position in China and globally.
Investment in AI and data center infrastructure is reshaping the global semiconductor demand, shifting capital toward advanced logic, memory, and advanced packaging. The industry is looking to key supplier for new technology, many of which have not yet been invented. ACM differentiated technology portfolio has been aligned well with this high-value process steps. Now the market is coming for us for solutions.
A good demonstration is recent momentum with several key global customer outside the mainland China market that we announced in today's press release. First, we announced that we have delivered multiple single wafer cleaning tools to Singapore facility of our Asia-based foundries customer. This marks ACM's first tool installation to Singapore, a key milestone for ACM. Second, we announced that we are receiving multiple orders for our advanced packaging tool from three global customers.
This include the orders for multiple wafer-level advanced packaging system from a leading global OSAT customer based in Singapore, with the delivers scheduled for the first quarter of 2026. A panel-level advanced packaging vacuum cleaning tool from a leading global semiconductor packaging manufacturer based outside mainland China, also scheduled for delivery in the first quarter of 2026.
Multiple wafer-level packaging system from a leading North America-based technology customer, with delivery scheduled later this year. Now on to our business result. Please turn to slide 3. For the fourth quarter of 2025, we deliver $244 million in revenue, up 9%. For the year 2025, we deliver $901 million in revenue, up 15%. Top-line growth of 15% was better than growth for the overall China WFE market, which third party estimate as generally flat for 2025. We consider this good result, especially since our 2025 revenue include very little contribution from our new products.
We expect a strong product cycle in 2026 from SPM cleaning and our furnace product, as we made a very good technical progress for this new product across our customer base. We also made a good progress with our supercritical CO2 dry track, panel level plating, and PECVD, which we expect to contribute some more in 2026, but more in 2027 and beyond. Shipment for 2025 were $854 million versus $973 million. 2024 shipment increased 63% over the year, so we had a tough compare. We also had some shipment for new product pushed into 2026. Importantly, we expect the 2026 shipment growth to be higher than our 2026 revenue growth.
Growth margin was 41% for the fourth quarter and 44.5% for the full year. Q4 growth margin was slightly below our long-term target range of 42%-48%. We attribute the Q4 level to product mixing, including a few semi-critical product with a lower margin due to the competitive pressure, and also higher seasonal inventory provisions. We expect our lower growth margin to be temporary. We believe our new product ramp, combined with the product design and the supply chain initiative, will enable us to deliver the best product at a low cost. There's no changing to our long-term target model range of 42%-48%. Moving on. We ended the year with a net cash of $845 million, versus $259 million at the year end of 2024.
This balance sheet provides the foundation to continue our effort to develop world-class tools for the leading global semiconductor manufacturers. Before I review our product, I will provide our view on competitive dynamics in China and how we will win in this environment. We have recently seen a flood of new local entrants to the China capital equipment industry. In many case, there are 5 or more player going after a single point product, all with very similar design and performance.
We believe we will compete and win in China market because, number one, we have a differential technology with many product, almost the best in the world. Two, we have a deep portfolio of IP with strong protection in China. Three, our local customer demand the best technology in order to compete in the global markets. Now, I will provide detail on product.
Please turn to slide four. Revenue from single wafer cleaning, Tahoe, and semi-critical cleaning tool was $626 million, up 8% in 2025, and represent 69% of total revenue. We now estimate our cleaning portfolio addresses 95% of the application and process step, we are working on developing remaining solution that will bring us to 100% in 2026. We believe ACM now has the widest coverage of cleaning tool, far more extensive as compared to all competitors.
The 8% year-over-year growth in 2025 included very little contribution from our newer cleaning line. We expect this new product, including single wafer SPM, Tahoe, and N2 bubbling wet etch, to contribute more meaningfully to our 2026 revenue. As the industry moves to more advanced nodes, we expect increased demand for high performance cleaning tools.
The increased adoption of multiple patterning is driving higher layer counts, potentially impact yields, and it demand more cleaning steps with a higher cleaning efficiency. We believe this plays right into ACM's strengths. For example, our proprietary N2 bubbling etching technology is uniquely positioned in the market. We are seeing growth, interest for advanced 3D NAND application, where larger bubble size and the uniformity control will become more critical as the industry moves to 300 layer and above.
Thank you, David. Good day, everyone. Please turn to slide 11 and 12. Unless I note otherwise, I'll refer to non-GAAP financial measures, which exclude stock-based compensation, unrealized gain loss on short-term investments. Reconciliation of these non-GAAP measures to comparable GAAP measures is included in our earnings release.
Unless otherwise noted, the following figures refer to the fourth quarter and full year of 2025, and comparisons are with the fourth quarter and full year of 2024. I will now provide financial highlights. Revenue was $244 million for the fourth quarter, up 9.4%. For the full year, revenue is $901.3 million, up 15.2%. Full year revenue was in line with our original guidance set a year ago and slightly above the updated range announced on January 22nd.
Fourth quarter revenue for single wafer cleaning, Tahoe, and semi-critical cleaning was $159.9 million, up 3%. For the year, this category grew by 8.1%. Fourth quarter revenue for ECP, front-end packaging, furnace, and other technologies was $64.1 million, up 23.9%. For the year, this category grew by 32.1%.
Fourth quarter revenue for advanced packaging, excluding ECP, services, and spares, was $20.5 million, up 23.8%. For the year, this category grew by 45.3%. I will now provide revenue mix by customer type for 2025. Starting this year, rather than disclosing specific customer names, we are now disclosing revenue by customer type once a year. For each customer type, this includes products, services, and spare parts.
We've included the mix table on slide seven of our presentation. For 2025, our revenue mix by customer type was split among foundry, logic, and other 59%, memory 27%, packaging and wafer processing 14%. 2025, we had four, 10+% customers, including our top customer was 16.9%, next was 13.5%, then 11.6%, and 10.2%, for an aggregate total of four customers representing 52.2% of total sales. For 2024, we had four, 10% customer, also for a total of 52.2%. Total shipments were $228 million for the fourth quarter, down 13.5%, and $854 million for the full year of 2025, down 12.2%.
David noted we had a tough compare versus a strong 2024, when shipments increased 63% year-over-year. We also did have some shipments for new products pushed into 2026. We expect 2026 shipment growth rate to be higher than our 2026 revenue growth rate. Gross margin was 41.0% for the fourth quarter, and 49.8%. For the full year, gross margin was 44.5% versus 50.4% in 2024. Q4 gross margin was slightly below our long-term target model. Adding to David's earlier remarks, gross margins were down 8.8 percentage points year-over-year on a quarterly basis.
This was due to product mix and margin pressure concentrated in a few semi-critical products, which contributed about 5 points of the headwind, and a higher level of inventory provisions that contributed about 4%, 4 points negative impact. As David noted, we expect the lower gross margins to be temporary.
We believe our new product ramp, combined with supply chain initiatives, will enable us to deliver the best products at a low cost, and there is no change to our long-term target model range of 42%-48%. For modeling purposes, we expect gross margins to be at the lower end of this longer-term target range for the first half of 2026, with an anticipated lift in the second half, due in part to contribution from newer products, which generally have higher gross margins.
Operating expenses were $70.6 million for the fourth quarter, up 21%. For the full year, operating expenses were $258.4 million, up 34%. For 2025, R&D was 15.1% of sales and marketing was 7.8% of sales, and G&A was 5.8% of sales. For 2026, we plan for R&D in the 16%-18% range, sales and marketing in the 7%-8% range, and G&A in the 6% range. Operating income was $29.5 million for the fourth quarter versus $52.8 million. Operating margin for Q4 2025 was 12.1% as compared to 23.6%. For the full year, operating margin was 15.9% as compared to 25.6%.
Long term, we look to grow our R&D spending in line with revenue, but we expect to show operating leverage in SG&A, with spending growth below our revenue growth level. Income tax expense was $6.6 million for the fourth quarter versus $17.3 million. For the full year, income tax expense was $13.3 million versus $35 million in 2024. For 2026, we expect our effective tax rate in the 8%-10% range. Net income attributable to ACM Research was $17.3 million for the fourth quarter versus $37.7 million. For the full year, net income attributable to ACM Research was $110.2 million versus $152.2 million. Net income for diluted share was $0.25 for the fourth quarter versus $0.56.
For the full year, net income per diluted share was $1.61 versus $2.26. Our non-GAAP net income excluded $6.4 million of stock-based compensation expense for the fourth quarter and $33.6 million for the full year. I will now review selected balance sheet and cash flow items. Cash, cash equivalents, restricted cash, and time deposits were $1.13 billion versus $441 million at year-end 2024. Net cash, which excludes short-term and long-term debt, was $845.5 million versus $259.1 million at year-end 2024. $585.4 million increase in net cash for 2025 included $623 million net raised in the private offering by ACM Shanghai in 2025.
Total inventory at year-end was $702.6 million versus $676.4 million at the end of the third quarter. Raw materials were $349.7 million, up $23.5 million quarter-over-quarter. We made additional strategic purchases to support production plans and to mitigate any potential supply chain risk. Work in process was $61.4 million, up $1.9 million quarter-over-quarter. Finished goods inventory was $291.6 million, up $0.9 million quarter-over-quarter. Finished goods inventory primarily consists of first tools under evaluation at our customer sites, along with finished goods located at ACM's facilities. Cash provided by operations was $33.9 million for the fourth quarter. For the full year, cash 2025, cash used by operations was about $10 million.