The Few Bets That Matter
Concentrated Equity Investor, AI Infrastructure
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.comÂ
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.comÂ
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.comÂ
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.comÂ
AXT's Q2 2026 results confirm its role as an upstream indium phosphide supplier to AI optical modules. Revenue rose 164% year on year to $47.6 million, well above $30.4-34.1 million consensus, with GAAP net income of $11.1 million and adjusted EPS of $0.19 versus $0.07 expected. Lumentum signed an InP substrate capacity reservation through 2031 with $87 million of prepayments. InP revenue hit a record and backlog topped $100 million as data-center links move to 800G and 1.6T. x.comÂ
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.comÂ
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.comÂ
AXT stays central to the InP substrate thesis because Coherent's 6-inch ramp relieves only its own device capacity and pushes the constraint upstream to substrates. Coherent does not plan to sell InP lasers externally soon, so the merchant shortage persists, which is also the context for Lumentum's long-term agreement with AXT. AXT's InP is made in Beijing, and China's InP export licensing remains despite the topic being raised in the Trump-Xi talks, so permission is the key variable. x.com … Show more
Applied Optoelectronics might be the best opportunity right now amid a potential laser-supply bottleneck: AleaBitOfReddit reports that Lumentum's CEO said it was effectively sold out through nearly 2029, with hyperscaler demand visibility into 2030-31. That shortage could benefit AAOI. x.comÂ
AXT's bottleneck thesis does not hold, because AXT is not even the number-one player in its market. Sumitomo Electric can bring new capacity online within 18 months. x.com x.comÂ
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
