STMicro's AI and Satellite Engine Is Outrunning Its Gross Margin

A $20 billion backlog and a doubling data-center ambition make the revenue story sing; the 44-46% margin target remains a 2027-28 promise.

STM · Earnings Call · 2026-10-29

The order book is no longer cyclical

STMicro's Q3 was a clean beat: net revenue of $3.76 billion came in above the midpoint, gross margin was 37.3%, non-GAAP EPS was $0.37, and free cash flow was $351 million. Q4 is guided to $4.15 billion, up 10.5% sequentially and 24.7% year-over-year, with gross margin around 39%; the full-year revenue guide is about $14.5 billion, up 22.8%. But the number that matters most is the order book. Jean-Marc Chery described “book-to-bill remaining well above 2 overall ... significantly above 2 in Communication Equipment and Computer Peripheral and Industrial” — Jean-Marc Chery, President and Chief Executive Officer · 2026-10-29. Backlog is “well above $20 billion ... about 5 quarters of revenue” — Jean-Marc Chery, President and Chief Executive Officer · 2026-10-29. That is a very different company from the one that spent 2025 talking about inventory correction and capacity reservation fees. The segment detail shows where the torque is coming from. RF & Optical Communication grew 46.2% year-over-year, Embedded Processing 24.1%, Power & Discrete 11.3%, and Analog/MEMS/Sensors 8.8%. By end market, Communication Equipment and Computer Peripheral rose 64%, Industrial 40%, Automotive 5%, while Personal Electronics fell 4%. Industrial is in a broad cyclical recovery, with distribution inventory below target and book-to-bill well above 3. AI datacenter and LEO are the company-specific growth driver that turns a recovery into a re-rating candidate.

AI datacenter and satellites: the numbers got bigger and harder to supply

Management now expects about $1.3 billion of AI datacenter revenue in 2026, 85% from MDRF — microcontrollers, silicon photonics, electronic ICs and BiCMOS. Chery said “this year, we will generate about $1.3 billion revenue for datacenter ... Next year ... well above doubling this number” — Jean-Marc Chery, President and Chief Executive Officer · 2026-10-29. That is a raise from the April call, when the company said “we confirm the revenue nicely well above USD 500 million” — Jean-Marc Chery, President and Chief Executive Officer · 2026-04-23 for 2026 and 'well above $1 billion' for 2027. The prepared remarks put 2027 at 'well above $2 billion'; the Q&A says 'well above doubling' the $1.3 billion base. Both are bullish, but the gap is one investors will press in January. LEO is the other unique leg. The Low Earth Orbit satellite communication business had a record year, and Remi El-Ouazzane said “next year, we are most likely going to be capacity gated not demand-gated” — Remi El-Ouazzane, President, Microcontrollers and Digital ICs · 2026-10-29. The technology anchor is Silicon photonics on 12-inch wafers, where ST says it is 'probably the only at-scale 12-inch SiPho player shipping right now' and is increasing capacity more than 4x year-on-year. This is not sector boilerplate: the broader AI data center basket in Know Trend's tape has cooled over the last 90 days, with 49 negative contributors against 7 positive. ST's company-specific guide is moving the other way.

The margin bridge is the swing factor

Revenue is clean; margin is not. Q3 gross margin was 37.3%, up 410 basis points year-over-year; Q4 is guided to about 39% on $4.15 billion of revenue. In April, Lorenzo Grandi framed the path as “when the company ... will be with revenues above $4 billion quarterly revenues ... we expect to have our gross margin at 40%” — Sandeep Deshpande, Analyst · 2026-04-23. Q4 is above $4 billion and the guide is 39%, not 40%. On Q1, Grandi would only say “we see gross margin at least at the current consensus for Q1” — Lorenzo Grandi, President and Chief Financial Officer · 2026-10-29 — roughly 38% — despite an 86-day quarter. That is an unusual way to guide. Leaning on current consensus rather than giving a range is why Didier Scemama pushed back:

you just said a number of things which are, in my understanding, contradictory to what you said before.
Didier Scemama, Analyst · 2026-10-29

The confusion is the story. The company is asking investors to underwrite a target model of 44-46% gross margin, but the bridge depends on closing four legacy fabs and completing the manufacturing reshaping program. Management says that delivers more than 400 basis points of structural improvement as a step function “toward the end of 2027 or in early 2028” — Lorenzo Grandi, President and Chief Financial Officer · 2026-10-29. Until then, input cost inflation and selected price increases are a partial offset; Q4 carries about 40 basis points of unused capacity charges and about 30 basis points of nonrecurring extra cost. Power & Discrete operating margin is still negative 17.1% — the transition cost is not theoretical.

What changed versus the prior calls

Three contrasts matter. Personal electronics: in January management expected to keep growing in 2026, “driven by our main customer” — Jean-Marc Chery, President and Chief Executive Officer · 2026-01-29; in Q3 it was down 4% year-over-year, though management insists there was no pull-in. Automotive: in October 2025 the auto guide was being dragged by capacity reservation fees and one EV customer; now auto is stable sequentially, up 5% year-over-year, with silicon carbide up about 20% this year and European electromobility accelerating. AI datacenter: the number has been raised twice in six months. The drivers are not new — they have been on the call for several quarters — but the magnitude and the capacity constraint are. The risk is that the margin line does not keep pace with the revenue line; the opportunity is that the 2027-28 step-up is exactly the kind of inflection that re-rates a semiconductor name. For now, STMicro is a high-visibility revenue compounder with a low-visibility margin bridge.