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 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 

IQE's 43% first-half revenue growth overstates the recovery, because the group is still slightly smaller than two years ago. Photonics is a genuine breakout at £38.5m, 44% above H1 2024, but wireless at £26.0m remains a third below that level and is still recovering. A £4.0m working-capital outflow absorbed the margin gain, 61% of May's £81m raise went to lenders, and depreciation runs about nine times capex. Converted InP lines delivering H2 volume without more capex would prove efficiency. … Show more

MACOM is a hold amid the AI sector sell-off: its investment in IQE de-risks operations a lot, but Coherent and Lumentum are better ways to play the 800G and 1.6T transition. x.com 

IQE's overhang has cleared: its £81 million raise is complete and brings in MACOM as a heavyweight strategic investor. The money goes straight to repaying debt, easing the balance-sheet pressure the market feared most, and the strategic review has ended, so IQE is no longer in limbo as a sale candidate. As the global leader in compound semiconductor epiwafers, its position in AI infrastructure, especially HBM4, and 5G is irreplaceable, and the valuation repair is just beginning. x.com 

MACOM is a key optical component supplier for Google's TPUs at a time when Google wants as many TPUs as it can get. The whole supply chain keeps beating quarter after quarter, underpromising and overdelivering on capacity increases, while MACOM is under the radar, underowned and still guiding very conservatively. A high P/E is justified if the market is underestimating future growth, and the stock is setting up to smash; pullbacks are buying opportunities. x.com  x.com  x.com 

MACOM is priced for perfection after going all-in on the second half. A $100M+ drop in cash went into a big inventory build of finished goods for 800G and 1.6T shipments, so if hyperscaler demand from Meta or Google softens even 5%, it could be left holding expensive specialized chips, and Q3 EPS guidance of $1.31-1.37 is wound tight. The quarter did show real execution: 800G LPO adoption has begun, data center guidance rose to about 40% growth, and its analog moat looks wider than feared. x.com 

IQE is the real business in its part of the compound-semiconductor chain, trading at about 6x sales with positive EBITDA. AXT, the substrate maker one layer upstream, trades above 50x sales on a 12.7% gross margin, which is pure narrative premium. Per @mkfilko, IQE grows the epitaxy that does the work on top of that substrate and grows revenue faster than AXT, though some of the gap is real given AXT's substrate duopoly and cleaner AI-optical story. 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