@KochuK thank you so much for your response. I do have one followup question though.
You write "If this ADR conversion fee is ordinary and necessary in order for you sell the shares via your US brokerage in the future, I would agree to add to the cost basis.".
My US brokerage (Interactive Brokers) allows me to buy and sell shares on the London Stock Exchange (and other foreign exchanges), so this ADR conversion isn't necessary to be able to dispose of the shares in the future.
Converting those shares to ADRs however makes it easier to do sell them in the future should I ever decide to switch to a different broker who does NOT offer international trading, because I will be able to use a U.S. exchange to sell the ADRs. Also I do not have to deal with foreign currency conversion anymore for dividend payouts and sales.
If I understand you correctly though, that means your criteria isn't met and I should not add the SDRT to my cost basis. Is that correct?
