I don't understand the bit about "recourse od action" - anybody who make a profit on capital assets (e.g. shares) is assessable for Capital Gains Tax - a self assessment tax. If, after assessment, it turns out that CGT is due then there is no option but to pay it. CGT is a self assessment tax but in the case of FA Revenue have acted unilaterally in writing to former shareholders outlining their calculations of the tax due. If you had no other share dealings in the past then this estimate of the tax due is probably correct. See this topic for more information on the FA CGT issue: