[tristanj]

From the wikipedia page on EUV: https://en.m.wikipedia.org/wiki/Extreme_ultraviolet_lithogra...

> To address the challenge of EUV lithography, researchers at Lawrence Livermore National Laboratory, Lawrence Berkeley National Laboratory, and Sandia National Laboratories were funded in the 1990s to perform basic research into the technical obstacles. The results of this successful effort were disseminated via a public/private partnership Cooperative R&D Agreement (CRADA) with the invention and rights wholly owned by the US government, but licensed and distributed under approval by DOE and Congress.[3] The CRADA consisted of a consortium of private companies and the Labs, manifested as an entity called the Extreme Ultraviolet Limited Liability Company (EUV LLC).[4]

> In 2001 SVG was acquired by ASML, leaving ASML as the sole benefactor of the critical technology.

Unless the situation has changed, the IP is still owned by the US government, and is licensed to ASML through their acquisition of Silicon Valley Group.

[dkjaudyeqooe]

Those early patents have likely expired.

[count]

The ITAR licensing around their export from the United States and the conditions under which they may be (including flowing down the restrictions clauses) don't expire, generally.

[belter]

From your own reference ( note this had 18 years of R&D by ASML ):

"By 2018, ASML succeeded in deploying the intellectual property from the EUV-LLC after several decades of developmental research, with incorporation of European-funded EUCLIDES (Extreme UV Concept Lithography Development System) and long-standing partner German optics manufacturer ZEISS and synchrotron light source supplier Oxford Instruments..."

[ckastner]

> By 2018, ASML succeeded in deploying the intellectual property from the EUV-LLC

That explicitly says that the IP is with EUV-LLC (edit: which is of U.S. origin).