Micron (MU): What This Company Actually Does

How Micron makes money

Micron designs and manufactures memory chips — DRAM (which computers use as fast, temporary working memory) and NAND flash (which stores data permanently, as in an SSD) — in its own network of fabrication plants, then sells them to computer makers, phone makers, data-center operators, and automakers. Unlike processor makers such as Nvidia or AMD, Micron's products are close to a commodity: a gigabyte of DRAM from Micron does largely the same job as one from Samsung or SK hynix, so price and manufacturing scale, not brand, usually decide who wins an order.

FY2025 capital spending was $15.9B, almost entirely reinvested into building more of this same fab capacity. Source: 10-K FY2025, p.7 (segment description), p.51 (capex guidance).

The AI boom, in real time

Source: Micron Q3 FY2026 earnings press release (2026-06-24), sec.gov/Archives/edgar/data/723125/000072312526000013/a2026q3ex991-pressrelease.htm.

Where the revenue comes from

Segment-level operating margins aren't separately disclosed. Source: 10-K FY2025, p.9-12.

Geographically (FY2025, by customer headquarters): the U.S. is 64.5%, Taiwan 15.2%, mainland China 7.1%, and other regions (Asia-Pacific, Hong Kong, Japan, Europe) 13.2%.

Source: 10-K FY2025, p.97 (Note 29, geographic information), p.44 (shipment destination).

Customers and competitors

Customer concentration has risen sharply and fast: in FY2023, no single customer accounted for 10% or more of revenue. By FY2024, one customer reached 10%. By FY2025, one customer — concentrated mostly in CMBU, i.e. AI data-center and HBM demand — accounted for 17%. Filings don't name this customer.

• Samsung Electronics — the memory industry's #1 player, with dominant scale in both DRAM and NAND that gives it a persistent cost advantage.
• SK hynix — the clear leader in AI-server HBM (high-bandwidth memory) and Micron's most direct rival for that specific, currently highest-margin product line.
• Kioxia / SanDisk — NAND flash specialists (descended from Toshiba's former memory division), a key swing factor in NAND pricing.

Source: 10-K FY2025, p.97 (Note 28, customer concentration), p.8 (competition).

The metric that matters most in this sector

Memory is a boom-and-bust commodity business, and inventory is the earliest warning sign of the bust. Days Inventory Outstanding (DIO = inventory ÷ cost of goods sold × 365) shows how many days of unsold product are sitting on the balance sheet — when it climbs, a price collapse has historically followed within a few quarters.

Inventory built for two straight years (94.8 to 180.5 days) into FY2023, right as prices collapsed and Micron posted its worst loss on record. It has since fallen for two straight years as the AI-driven shortage worked through the system — consistent with, though not proof of, the current upcycle.

Source: annual 10-K balance sheets and income statements — FY2021 p.62, FY2022 p.60, FY2023 p.62, FY2024 p.60, FY2025 p.64.

Leadership and ownership

CEO Sanjay Mehrotra has led Micron since May 2017 and added the Chairman title in January 2025. He is not a Micron founder — he co-founded SanDisk in 1988 and ran it until its 2016 acquisition by Western Digital, giving him decades of memory-industry experience before joining Micron. Combined insider ownership is low, about 0.24% (2,686,052 shares of 1.124 billion outstanding). The largest shareholders are all institutional: Vanguard (8.4%), BlackRock (7.6%), and Capital World Investors (6.3%).

Source: DEF 14A, filed 2025-11-25 (ownership table as of Oct 31, 2025).

Capital returns

Micron pays a quarterly dividend of $0.115/share ($0.46 annualized) — against the current price of $932.86, that's a yield of roughly 0.05%, essentially immaterial. The dividend program only began in 2021 and the payout ratio remains very low.

Buybacks have shrunk to nothing just as they'd matter most: $425M in FY2023, $300M in FY2024, and $0 in FY2025 — leaving $7.19B spent against a $10B authorization approved back in 2019.

Source: 10-K FY2025, p.44 (dividend declaration, Sept 23, 2025), p.44-45 (financing activities), p.83 (diluted share count).

How this company could fail

• Memory pricing-cycle risk — DRAM and NAND behave like commodities: even modest oversupply crashes prices quickly. FY2023 saw revenue fall 49.5% and an operating loss of $5.7B. Today's extraordinary margins should not be assumed to be the new steady state.
• China and geopolitical risk — China's Cyberspace Administration (CAC) barred certain domestic critical-infrastructure operators from buying Micron products in 2023, and U.S.-China semiconductor export controls keep expanding, including a Section 232 tariff investigation the Commerce Department opened in April 2025.
• Customer concentration risk — from no customer above 10% of revenue in FY2023 to one customer at 17% in FY2025, Micron's dependence on a small number of AI hyperscalers is rising quickly; a single customer trimming orders could now move results meaningfully.

Source: 10-K FY2025, p.8 (Item 1A risk factors), p.51 (industry conditions).

Five-year financials

Operating income and revenue: 10-K FY2025 p.42, FY2022 p.42. FCF = operating cash flow minus capex (10-K FY2025 p.44). Debt and cash: 10-K FY2025 p.43 (balance sheet), p.86 (Note 12, debt).

What we still don't know

• Whether Micron actually hit its FY2026 Q4 guidance (~$50.0B revenue, ~86% gross margin) can't be confirmed from this data alone — full FY2026 results (fiscal year ended late August 2026) hadn't been reported as of this card's writing.
• Whether the current ~84% gross margin is structural or cyclical isn't something the filings alone can settle — Micron's five-year average gross margin was in the high-20s%, far below today's level.
• Which specific customer drove the jump to 17% of FY2025 revenue isn't named in the filings (widely presumed to be an AI-server buyer, but unconfirmed).