Hi Argentina
Your question is very interesting and is very technical. How much did your brother invest? Is it worth paying for tax advice?
In 2009 he made an investment. In reality, it was lost immediately, so he should argue that he made a CGT loss in 2009.
In 2010 he made a Capital Gain for tax purposes.
If he had recognized the loss in 2009, he should have been able to bring the loss forward against his gains in 2010.
There were/are some very specific rules about claiming for losses where an investment value has been written off completely. I think that he must notify the Revenue of his intention to claim the loss in the year that he is making the claim. In other words, if he wanted to claim the loss in 2009 he would have had to notify the Revenue in that year.
It's a very interesting problem which I have not come across before and there may well be Revenue guidance on it.
Brendan