I am interested in buying US single company shares through my ISA. However I’m concerned this won’t be as simple as holding Shares that are listed in the UK and there will be additional forms to complete as US taxes to pay? I say this as I purchased shares in my US listed employer through a company scheme and there was something called a W5 withholding form/tax and I really didn’t want the hassle. I prefer to keep my tax affairs as simple as possible so I sold them after a month. Any advice?