EUV - extreme ultraviolet lithography - is the technique used to print the smallest features on leading-edge chips, using 13.5-nanometer light produced by vaporizing tin droplets with a laser. ASML is the only company in the world that builds EUV scanners. That makes its annual report unusually important: it is the formal record of a genuine chokepoint.
The filing is ASML's Form 20-F filed February 15, 2023 (sec.gov; accession 0000937966-23-000014), the annual report covering the prior fiscal year. As a Dutch company listed in the US, ASML files the foreign-private-issuer 20-F rather than a domestic 10-K - the same lane as TSMC.
Why study the chokepoint through its own filing? Because a single-supplier dependency concentrates risk and information in one place. Every leading-edge foundry's roadmap ultimately depends on ASML tool deliveries; the 20-F is where the company itself describes its business, its order position, and the risks around it for US investors.
The physics is what makes the monopoly durable. EUV requires a vacuum optical path, multilayer mirrors rather than lenses, and a plasma light source - an integration challenge no competitor has matched at production scale. The 20-F documents a business whose moat is decades of systems engineering, not a single patent.
For an explainer reader, the method is the message: to understand a chokepoint, go to the chokepoint's primary disclosure. The 20-F, filed as a foreign issuer, is where ASML's position is recorded on the public record - and knowing it is a 20-F is the first step to finding it.
The primary source is the sec.gov 20-F; it was located through EdgarBeast, an SEC-filing evidence index. The lithography bottleneck is best read where its owner discloses it - on Form 20-F.