The market is repricing the capex; the franchise is still expanding margin.

• The capex bill. Calendar-2026 capex guide jumped to $190B on the April 29 call — up 61% year-on-year and roughly $35B+ above prior consensus. Q3 FY26 free cash flow fell 22% to $15.8B even as net income rose 23%. Twenty-six of 38 sell-side firms cut price targets after the beat.
• The franchise. Operating margin expanded to 46.3% on +18% revenue in Q3. Productivity & Business Processes earned $69.8B of segment operating income at 57.8% margin in FY25. Commercial RPO is $627B, +99% year-on-year — the largest software backlog ever disclosed.
• What is actually being repriced. ROIC has fallen from 37% in FY21 to 24% in FY25; FCF margin from 33% to 25%. The question is whether AI revenue absorbs the AI capex before the 5-to-6-year asset lives become a write-down candidate.

Margin still expanding; returns on capital quietly halving.

Capex more than tripled in four years; depreciation jumped from $14B in FY22 to $34B in FY25 and is set to keep climbing as the FY24-26 build flows into the income statement. The bull case requires FCF to re-accelerate by FY27; the bear has 18 months of evidence ammunition before that inflection arrives. Stripping working-capital lifelines and the Activision close, organic FCF is closer to $55-60B than the headline $71.6B.

The seat franchise alone clears half the $3.1T quote at peer software multiples.

• What segment math says. Productivity & Business Processes earned $69.8B of operating income at 57.8% margin in FY25. At 20-25× — peer software-seat multiples — that one segment is worth $1.4-1.7T, or 45-55% of today's market cap.
• What is already in the price. Add ~$51B net cash plus a ~27% as-converted economic interest in OpenAI valued near $228B at OpenAI's reported $852B post-money valuation (Microsoft's own carrying-value disclosure pegs the stake at ~$135B), and the floor reaches $1.6-2.0T before Intelligent Cloud earns anything.
• What you are actually buying. The remaining $1.1-1.4T pays for Intelligent Cloud ($44.6B of operating income, Azure +40% in Q3 FY26), More Personal Computing ($14.2B), and the AI optionality the headlines are arguing about.

The captive supplier is no longer captive — and that may be the point.

• What changed April 27, 2026. Microsoft announced the next phase of the OpenAI partnership: Azure exclusivity removed (right of first refusal gone), OpenAI can now ship on AWS and Google Cloud, Microsoft no longer pays revenue share to OpenAI, and OpenAI's revenue share back to Microsoft is now capped through 2030. IP rights extend to 2032.
• What it touches. ~45% of commercial backlog was OpenAI-linked at the Q2 FY26 disclosure ($625B then; $627B at Q3); the non-OpenAI portion grew 28% year-on-year. The Musk v. Altman trial surfaced a 2022 Nadella email — 'better to be an investor and not even take all this execution risk' — that fits the new posture.
• Bull and bear of it. Bull read: Microsoft retains a $250B OpenAI Azure commitment, IP through 2032, and is freed from revenue share. Bear read: nearly half of contracted backlog is now non-exclusive, and Microsoft's internal Phi and MAI models are not yet credible on frontier benchmarks.

Worst quarter since 2008 — Ackman bought it, the Gates Trust sold it.

• The drawdown. From the October 28, 2025 closing peak of $542 the stock fell to a $357 low on March 27, 2026 — a ~34% drawdown. Q1 calendar-2026 was the steepest quarterly decline (~23%) since Q4 2008. The May 15 close at $421.92 has reclaimed roughly a third of the slide.
• The split tape. Bill Ackman built a Pershing Square position in Q1 (accumulation began February) at ~21× forward earnings, calling it a core holding and funding it by selling Alphabet. The Gates Foundation Trust completed a $3.2B exit (final 7.7M shares in Q1 2026); Chris Hohn's TCI divested most of its ~$8B stake.
• The decision date. Q4 FY26 prints late July 2026 (FY25 print was July 30, 2025). Three line items — Microsoft Cloud gross margin (FY25 was 69%; Q4 FY26 management guide ~66%), free cash flow growth, and the first FY27 capex framing — settle whether the build is absorbing depreciation or breaking the franchise.