30(1)The Commissioners for Her Majesty’s Revenue and Customs are not liable to give effect to a claim under paragraph 29 if or to the extent that the claim falls within a case described in this paragraph.
(2)Case A is where the amount of tax paid, or liable to be paid, is excessive because of—
(a)a mistake in a claim, or
(b)a mistake consisting of making, or failing to make, a claim.
(3)Case B is where the claimant is or will be able to seek relief by taking other steps under this Part of this Act.
(4)Case C is where the claimant—
(a)could have sought relief by taking such steps within a period that has now expired, and
(b)knew or ought reasonably to have known, before the end of that period, that such relief was available.
(5)Case D is where the claim is made on grounds that—
(a)have been put to a court or tribunal in the course of an appeal by the claimant relating to the amount paid or liable to be paid, or
(b)have been put to HMRC in the course of an appeal by the claimant relating to that amount that is treated as having been determined by a tribunal by virtue of paragraph 46 (settling of appeals by agreement).
(6)Case E is where the claimant knew, or ought reasonably to have known, of the grounds for the claim before the latest of the following—
(a)the date on which a relevant appeal in the course of which the ground could have been put forward was determined by a court or tribunal (or is treated as having been so determined);
(b)the date on which the claimant withdrew a relevant appeal to a court or tribunal;
(c)the end of the period in which the claimant was entitled to make a relevant appeal to a court or tribunal.
In this sub-paragraph “relevant appeal” means an appeal by the claimant relating to the amount paid or liable to be paid.
(7)Case F is where the amount in question was paid or is liable to be paid—
(a)in consequence of proceedings enforcing the payment of that amount brought against the claimant by HMRC, or
(b)in accordance with an agreement between the claimant and HMRC settling such proceedings.
(8)Case G is where—
(a)the amount paid, or liable to be paid, is excessive by reason of a mistake in calculating the claimant’s liability to tax, and
(b)liability was calculated in accordance with the practice generally prevailing at the time.
(9)Case G does not apply where the amount paid, or liable to be paid, is tax which has been charged contrary to EU law.
(10)For the purposes of sub-paragraph (9), an amount of tax is charged contrary to EU law if, in the circumstances in question, the charge to tax is contrary to—
(a)the provisions relating to the free movement of goods, persons, services and capital in Titles II and IV of Part 3 of the Treaty on the Functioning of the European Union, or
(b)the provisions of any subsequent treaty replacing the provisions mentioned in paragraph (a).