I'm looking into the possibility of buying shares using an app like Degiro or Bux Zero. I'm intending simply to buy and hold permanently with a view to building up a portfolio and either selling once I retire or possibly simply collecting dividends if any are forthcoming. Since my strategy will be to sit on anything I buy long term, I'm wondering if I am required to make yearly declarations to the Revenue about what I may be holding, or if I only need to declare to them if I either collect dividends or sell at a profit. Or do I need to declare also if I sell at a loss?