EUV and higher energy photons are difficult beasts, I would put my money on electrons next, so perhaps the electron microscope companies hold the interesting patents there.
My opinions is that this whole comment discussion about creating a competitor is in the wrong direction. It is impossible to recreate and outperform what ASML has.
A better focus would be to tackle problems in the <2nm processes. If someone found a method to stop electron tunneling at smaller nodes, this will net much more revenue and create more value for society.
