Likely the same thing that's caused Apple's stock to drop significantly yesterday and today - China has banned iPhones for government officials at work.
While that in and of itself isn't a huge problem, the broader concern is that this is part of a government effort to push homegrown phones (and chips). That's compounded by the fact that Huawei just revealed a phone with a 7nm chip, which is technology they weren't expected to have.
If the Chinese population moves to Chinese-made phones with Chinese-made chips, it'll certainly have a negative impact on ASML.
While that in and of itself isn't a huge problem, the broader concern is that this is part of a government effort to push homegrown phones (and chips). That's compounded by the fact that Huawei just revealed a phone with a 7nm chip, which is technology they weren't expected to have.
If the Chinese population moves to Chinese-made phones with Chinese-made chips, it'll certainly have a negative impact on ASML.