I have gone through the VAT related questions on the forum. It seems, the Dropbox admin is not getting the question. Hence, I am sending a copy of my Dropbox Pro invoice (which does not show Dropbox VAT number nor VAT separately) to HMRC (Tax Department in the UK) as it is a legal obligation in the UK to give a VAT receipt showing VAT number of the seller and VAT rate as well as amount. This is necessary for a business in the UK (and for that matter anywhere in Europe) to claim back the VAT paid on the service.
This is not applicable if Dropbox is not collection VAT but it is quite clear that they are charging VAT. Now if they are charging VAT, then they must remit VAT collected to the Office of Revenue Commissioners in Republic of Ireland and we as a user should be able to claim this VAT back if we are using the service for our business and we are VAT registered in any of the EU countries.
So it really surprises me to see the reluctance of Dropbox to simply resolve this issue by adding VAT details on the invoice (and it is not that they don't have this facility in their invoicing system because they are already providing VAT invoice for Dropbox for Business subscription)
I guess I will leave HMRC to deal with as they have gone quite strong now-a-days with issues like this.