Why Micron Just Became One of My Most Interesting Compounders to Watch

I've been watching Micron for a long time. Today's +19% move — taking the market cap past USD 1 trillion for the first time — isn't a surprise to me. What has surprised me is how fast the margin story has actually changed.

Let me walk through what I mean.

Micron's fiscal Q3 guidance calls for USD 33.5 billion in revenue at approximately 81% gross margins. Twelve months ago, gross margins for MU were in the 30s. Moving from the 30s to 81% in roughly four quarters is almost entirely explained by one product: high-bandwidth memory. HBM4, Micron's latest generation, began volume shipments in 2026. Micron is one of only three companies in the world capable of producing this at scale, and the pricing power that comes with that position is visible in every line of the income statement.

I look at this on Qualtrim, and the free cash flow trajectory for MU has shifted in a way I find genuinely interesting. This is a company that's starting to transition from a commodity cyclical to something that looks more like a structural AI infrastructure business. The memory cycle still exists — it always does. But HBM contracts are long-duration, tied to multi-year data centre buildouts, and they're not priced like DRAM spot markets. That changes the quality of earnings visibility.

AMD's +7% today is worth noting alongside this. AMD is winning AI accelerator share from hyperscalers, and more AI accelerators in data centres means more HBM demand. These two stories compound each other. I hold AMD as part of the same AI infrastructure thesis, and today's move reinforces that the underlying demand signal is real.

I'm not recommending anyone buy MU at today's price without doing their own research. But the earnings are real, the margin expansion is structural, and the AI memory cycle is still in early innings. This is the kind of business I want to understand better. That's what I'm focused on.