An EIS investment was done in 2012, that seems to have had an insufficient claim made. There is no record of the actual claim submission as it was done outside of the annual Self Assessment, by submitting pages 3&4 of the EIS Certificate and Claim Form sent by the company, of which no copy was kept. We can see from HMRC's portal account history though that a tax refund was given that corresponds to 9% of the investment. So it seems that the form was filled incorrectly at the time, and the field which asks what is the amount on which tax relief is claimed was filled with 30% of the investment amount (answering what is the amount of tax relief sought, not what is the amount on which tax relief is sought). The error was only found now, as the company went to administration, and EIS loss relief is sought and a check is made on whether tax relief was properly claimed upfront.
Can the original claim be amended? I realize it's now almost 8 years since then.
If not, what is the current situation? Is EIS loss tax relief to be sought on the total net loss of the investment minus the actual tax relief already given? So income tax relief on the remaining 91p per £1 of investment?