Self-assessment form for foreign company shareholder

Hi, HMRC admin, I would like to raise a question for a scenario: If a UK tax resident is a shareholder of a foreign company, will he/she have to submit a self-assessment form in the tax year ? In my understanding, as long as no dividend, selling of shares or incomes are inolved, submission of self-assessment form is not needed. Am i correct ? Further question is, what if the amount of shares he/she holds exceed certain level, say 30%, will that trigger any other relevant tax reporting process ? The director and major business is in the country where the company is registered. I guess that is more related to the tax residence problem of a company. How can the shareholder judge whether "central management and decision" is defined ? I don't see a clear line from any documents in HMRC website.

Hi,

Please refer to guidance here:

Tax on foreign income

Thank you.