⚠ Concentration Risk in the Critical LinksModerate threat

Controlling the irreplaceable components is a formidable moat, but it concentrates ASML's fate in a handful of critical, single-sourced links. If Zeiss cannot produce enough optics, or a problem emerges at Cymer's light-source operation, there is no second supplier to turn to — the same exclusivity that keeps competitors out also means ASML has no fallback if one of these chokepoints stumbles. The optics in particular are so difficult and slow to produce that Zeiss's capacity has, at times, been a genuine constraint on how many machines ASML can build.

This is the quiet operational risk beneath the strategic strength: a supply chain of a few irreplaceable partners, each making something no one else can, is powerful but brittle. A disruption at a key supplier — a technical failure, a capacity ceiling, a natural disaster at a critical facility — flows straight through to ASML's ability to deliver, with no alternative source to soften it. ASML manages this through deep integration, long-term investment in its partners' capacity, and in Cymer's case outright ownership¹, and the risk has never seriously bitten. But owning the chokepoints means owning their fragility too, and the machine's dependence on a few irreplaceable inputs is a concentration that the very depth of the moat creates.