Company Sale Tax Implications

I have worked full time overseas for over 10 years and filed tax returns abroad. When in the UK in the 90s I invested a stake in a startup company. Now it is being sold. What is my UK tax liability on the proceeds of the sale?

Hi,
You can see guidance here:
Capital Gains Tax: what you pay it on, rates and allowances
Thank you.

I am a non-resident and have been for over 10 years. Why then am I liable for CG Tax, which is what you sent me as guidance? Thanks

Hi 
You may still be liable if the item being sold is UK based as not all income is exempt under double taxation.
Thank you.