IQE is hard to call undervalued because its price already embeds a mature-margin scenario two-plus years out. At a 15% margin and 20% yearly growth, FY28 EBITDA is about GBP25 million, worth about GBP500 million at a generous 20x, versus a GBP520 million market cap at 40p. IQE earns about 3% adjusted EBITDA margins versus LandMark's high-margin epi, MACOM's convertible and warrants carry about 76 million shares of overhang, and InP supply constraints threaten its H2-weighted guide. x.com  x.com  … Show more

IQE's bottleneck position in AI optics is already priced in, so the easy money is gone until its revenue and profits grow. Per @jpinsights, IQE grows the indium phosphide epiwafers high-speed lasers are built from, and validation came through MACOM's GBP45m investment, Tower's multi-year supply deal and a GBP81m raise. But the stock has rerated hard, and it is unclear whether any of this has reached IQE's own numbers. x.com 

IQE's new multi-year indium phosphide epiwafer supply deal with Tower Semiconductor puts a 5x-10x move from March 2026 levels in the works, and IQE is the pick over Tower itself. Per Wall St Engine, the wafers support Tower's silicon photonics platforms for AI data center optics, including 200G/lane pluggable transceivers, 400G/lane modulator prototypes and optical circuit switches. The two also settled their IP dispute, with Tower granting IQE a worldwide royalty-free license. x.com  x.com 

IQE's outsourced epitaxy business is structurally disadvantaged because demanding optics customers want the whole chain under their own control. Big integrated players such as Lumentum and Applied Optoelectronics run their own reactors and want to control manufacturing conditions throughout. Shipping wafers to an outside fab for epi growth and back falls short of that ideal, so regardless of IQE's execution the business model is unappealing, even as @crux_capital_ turns more positive. x.com 

IQE is held above its fundamental fair value by optimistic expectations, and its takeover thesis is effectively dead. With MACOM as anchor investor holding board seats and exclusive long-term supply deals, a bidding war is practically ruled out. The 19.8p placing, a 58% discount, takes dilution since early 2025 to about 42%, and the £81 million mostly repays debt, so capex needs another raise within 18-24 months. If momentum fades the stock will fall; if it strengthens, it can keep rising. x.com 

IQE is reaching its financial inflection point as InP demand for AI and data centers drives growth. It raised 2026 revenue growth guidance from 20% to over 30% after H1 revenue of £64m versus £45m, and forecasts low-teens £m adjusted EBITDA. MACOM's investment left it debt-free with £42m of cash. The 30% target looks deliberately conservative after past over-optimism; as @mkfilko notes, it implies H2 revenue below H1, which seems unlikely. x.com  x.com 

Soitec is an attractive name in the photonics supply chain. Per @HyperTechInvest, it trades at 14x forward EV/EBITDA, the lowest among key photonics suppliers, versus 33x for Coherent, 45x for Lumentum and 120x for Applied Optoelectronics. @zephyr_z9 flags a risk of demand destruction in mobile. x.com  x.com 

IPG Photonics' old downtrend is over and its new uptrend is stable, making it more attractive than photonics peers that have already run far. Before the AI, photonics and defense wave, revenue was in persistent decline, profits and free cash flow were collapsing, and the company looked headed toward zero. Landing in the right sectors at the right time sparked a 200% rally, which earnings have since cooled. x.com 

IQE is priced for skepticism it no longer deserves, while Sivers Semiconductors is priced for perfection it has not delivered, though both sit in the same AI optical chain. Sivers trades at about 85x sales with negative EBITDA, and Q1 revenue missed. IQE trades near 4-5x sales, is EBITDA positive, guides 20%+ growth to at least £117M in 2026, has cleared bank debt with MACOM's backing, and trades far below peer LandMark at about 70x forward. Sivers is worth revisiting only if its price resets. … Show more

Sivers Semiconductors' $30M expansion of its Glasgow InP fab, targeting over 100M CW DFB lasers a year by Q4 2027, likely means hard dilution. As @PhotonCap notes, the plan shifts Sivers toward hybrid manufacturing, and its capacity target and customer ramps remain forward-looking rather than committed volumes. x.com