Firms fined for deliberate corporation tax misinformation hits four-year high Figures obtained by City AM reveal the number of businesses fined by HMRC for deliberately obscuring their corporation tax affairs has climbed to its highest level in four years. Last year, HMRC penalised 62 firms for purposefully sending incorrect information, up 35% from 46 the previous year. However, the average corporation tax penalty issued by the taxman fell 72% over the last year to £4,845, down from £17,454