AXT, Inc.

Business in one line

AXT grows single-crystal ingots of indium phosphide, gallium arsenide and germanium in China using proprietary vertical gradient freeze technology, slices them into wafer substrates, and sells them to epitaxial-layer houses that sell on to chip fabs. Consolidated Chinese subsidiaries also make purified gallium, pBN crucibles and InP base material, consuming some internally and selling the rest. In FY2025 substrates were 67% of $88.3 million of revenue, raw materials 33%.

Type · Cyclical  policy-gated upcycle

For a cyclical the bear case lives in the cycle and in what gets bought at the top, not in a competitor taking share.

Bull case vs. Bear case

Peter Lynch pitchThe simple reason this stock could work is that AI data centers move data with light, light needs indium phosphide lasers, and AXT is one of a handful of firms that can grow low-defect InP crystals — and after eighteen months locked behind China's export-permit gate, the permits started flowing and the business went from losing money to a 44.9% gross margin in five quarters.

Munger invertThe most likely way I lose money is that the 44.9% margin quarter turns out to be the peak of a policy-driven catch-up — in a business whose revenue gate is held by a government with a stated interest in building the domestic industry its customers compete with.

Why the market might be missing it: AXT reports one operating segment and never discloses InP revenue, volumes or pricing, so the mix shift was invisible in the reported lines until it arrived all at once in consolidated gross margin — and the commitments underwriting 2027 sit in 8-Ks, not the P&L. But the stock was sold at $12.25 in December 2025 and $64.25 four months later, so the argument is not that the market missed the cycle. It is about how long the margin lasts and what the capital earns.

Signals to monitor

Each signal tracks a named assumption or risk. A signal that tracks nothing in this memo is noise.

External challenge notes

Omitted — external search was not requested for this run. Ask for “external challenge” to add competitor, regulatory, litigation and short-seller findings here, kept separate from company-source evidence.

Bottom line