AXT supplies the InP substrates that expanding optical manufacturing requires. It supplies every manufacturer, and that demand will take its shares to new all-time highs. Applied Optoelectronics is expanding capacity and selling the most cost-efficient product; a quoted post reports that Lumentum's CEO said his firm is effectively sold out through nearly 2029. x.com 

AXT's indium phosphide substrate chokepoint gives it pricing potential, though its Coherent agreement caps annual wafer-price increases. Channel checks suggest increases of 50-60% in Q2 2026, 10% in Q3 and over 10% in Q4. With supply agreements to Lumentum and Coherent, AXT probably becomes No. 1 ahead of Sumitomo Electric. A SanDisk-style hike now looks less likely because of the annual cap, whose percentage is redacted. x.com 

AXT's permit-backed Q4 outlook weakens the near-term operating objection to the Sell case. Q3 revenue reached $73.4M at 56% GAAP gross margin; management guides to about $90M in Q4 from business permitted or not needing permits. InP contributed $54.3M and backlog exceeds $500M, though much spans years. The remaining test is whether 2027 capacity becomes qualified, permitted shipments at durable margins. x.com  x.com  x.com 

AXT is the upstream chokepoint of the photonics buildout, supplying the indium phosphide substrates every high-speed laser needs amid a massive global shortage. About 600,000-700,000 wafers shipped in 2025 against demand of 1.5-2 million, and AXT holds roughly 36% of a market three firms control. Record revenue rose 164% to $47.6M and gross margin hit 45% from 8.2%; Lumentum prepaid $87M to reserve capacity through 2031. The real risk is China, where slow export permits caused a guidance miss. … Show more

AI bandwidth demand still favors Coherent and Lumentum, but tight customer financing can delay orders and lasting valuations need durable profits. A model provider losing share need not reduce total bandwidth use. Coherent could beat and raise guidance; Lumentum may only meet estimates this quarter, improving next quarter. If margins partly reflect scarce indium phosphide, added supply will test whether upgrades, volume and cost gains sustain earnings. These earnings calls remain forecasts. … Show more

Lumentum and Coherent are investments driven by product iteration, while AXT is a bottleneck trade best treated as speculation. Shortage-driven price hikes on the same parts define a cyclical stock, prices quickly discount shortage expectations, and once profits truly climb it is time to exit. Bottlenecks also push customers to design around them and invite new entrants. Investable companies keep lifting margins through yield gains and new products, driving token deflation while growing revenue. … Show more

InP substrate demand and pricing still support the AI optics supply chain. Yunnan Germanium reports higher InP volumes from AI data centers and optical communications, plus higher prices. Q3 revenue rose 134.6% year on year, near AXT's guided 136%, but also includes germanium. IQE's H1 photonics grew 45%, partly from US defense funding. AXT's $66m Q3 guide covers only licensed exports or sales needing no license; a miss would more likely reflect licensing. x.com 

Optics and photonics should be among AI's biggest winners as faster GPU networks need optical connections that suppliers cannot expand quickly enough. Lumentum says some components are sold out through early 2029; Sivers is investing $30M to target more than 100M lasers a year, with operations expected in Q4 2027. Potential US restrictions on Chinese transceivers could reshape supply in 2027. Applied Optoelectronics and Sivers are the favorites. x.com  x.com 

AXT cannot be the dominant indium phosphide substrate supplier when its customers' supply depends on the Chinese government's export permitting. Lumentum has locked up InP supply for several years with Sumitomo, a larger competitor that does not face the same export restrictions. Doubling down on manufacturing in China is an odd choice given continuous permitting roadblocks. Substrate pricing is unlikely to go parabolic, despite Serenity's claims of 10x+ price increases. x.com  x.com 

Applied Optoelectronics should trade above $150, in part because Lumentum's CEO says its optical components are sold out through early 2029 and it cannot meet roughly 70% of demand for some products through 2027. That industry signal strengthens the case for AAOI's expanding 800G/1.6T offerings after completion of its $600M ATM, with shares around $110. x.com