A statute granting tax exemption is strictly construed against the person or entity claiming the exemption.

See -  http://sc.judiciary.gov.ph/jurisprudence/2012/june2012/181136.htm

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Being a derogation of the sovereign authority, a statute granting tax exemption is strictly construed against the person or entity claiming the exemption. When based on such statute, a claim for tax refund partakes of the nature of an exemption. Hence, the same rule of strict interpretation against the taxpayer-claimant applies to the claim.[14]

In the present case, petitioner’s claim for a refund or tax credit of input VAT is anchored on Section 112(A) of the NIRC, viz:

Section 112. Refunds or Tax Credits of Input Tax. -

(A) Zero-rated or Effectively Zero-rated Sales. - any VAT-registered person, whose sales are zero-rated or effectively zero-rated may, within two (2) years after the close of the taxable quarter when the sales were made, apply for the issuance of a tax credit certificate or refund of creditable input tax due or paid attributable to such sales, except transitional input tax, to the extent that such input tax has not been applied against output tax: Provided, however, That in the case of zero-rated sales under Section 106(A)(2)(a)(1), (2) and (B) and Section 108 (B)(1) and (2), the acceptable foreign currency exchange proceeds thereof had been duly accounted for in accordance with the rules and regulations of the Bangko Sentral ng Pilipinas (BSP): Provided, further, That where the taxpayer is engaged in zero-rated or effectively zero-rated sale and also in taxable or exempt sale of goods of properties or services, and the amount of creditable input tax due or paid cannot be directly and entirely attributed to any one of the transactions, it shall be allocated proportionately on the basis of the volume of sales.

Thus, a taxpayer engaged in zero-rated or effectively zero-rated sale may apply for the issuance of a tax credit certificate, or refund of creditable input tax due or paid, attributable to the sale.

In a claim for tax refund or tax credit, the applicant must prove not only entitlement to the grant of the claim under substantive law. It must also show satisfaction of all the documentary and evidentiary requirements for an administrative claim for a refund or tax credit.[15] Hence, the mere fact that petitioner’s application for zero-rating has been approved by the CIR does not, by itself, justify the grant of a refund or tax credit. The taxpayer claiming the refund must further comply with the invoicing and accounting requirements mandated by the NIRC, as well as by revenue regulations implementing them.[16]

Under the NIRC, a creditable input tax should be evidenced by a VAT invoice or official receipt,[17] which may only be considered as such when it complies with the requirements of RR 7-95, particularly Section 4.108-1. This section requires, among others, that “(i)f the sale is subject to zero percent (0%) value-added tax, the term ‘zero-rated sale’ shall be written or printed prominently on the invoice or receipt.”

We are not persuaded by petitioner’s argument that RR 7-95 constitutes undue expansion of the scope of the legislation it seeks to implement on the ground that the statutory requirement for imprinting the phrase “zero-rated” on VAT official receipts appears only in Republic Act No. 9337. This law took effect on 1 July 2005, or long after petitioner had filed its claim for a refund. 

RR 7-95, which took effect on 1 January 1996, proceeds from the rule-making authority granted to the Secretary of Finance by the NIRC for the efficient enforcement of the same Tax Code and its amendments. In Panasonic Communications Imaging Corporation of the Philippines v. Commissioner of Internal Revenue,[18] we ruled that this provision is “reasonable and is in accord with the efficient collection of VAT from the covered sales of goods and services.” Moreover, we have held in Kepco Philippines Corporation v. Commissioner of Internal Revenue[19] that the subsequent incorporation of Section 4.108-1 of RR 7-95 in Section 113 (B) (2) (c) of R.A. 9337 actually confirmed the validity of the imprinting requirement on VAT invoices or official receipts – a case falling under the principle of legislative approval of administrative interpretation by reenactment.

In fact, this Court has consistently held as fatal the failure to print the word “zero-rated” on the VAT invoices or official receipts in claims for a refund or credit of input VAT on zero-rated sales, even if the claims were made prior to the effectivity of R.A. 9337.[20] Clearly then, the present Petition must be denied.

In addition, it is notable that the CTA Second Division and the CTA En Banc, including Presiding Justice Acosta in his Concurring and Dissenting Opinion, both found that petitioner failed to sufficiently substantiate the existence of its effectively zero-rated sales to NPC for the 3^rd and 4^th quarters of taxable year 1999, as well as all four quarters of taxable year 2000. It must also be noted that the CTA is a highly specialized court dedicated exclusively to the study and consideration of revenue-related problems, in which it has necessarily developed an expertise.[21] Hence, its factual findings, when supported by substantial evidence, will not be disturbed on appeal.[22] We find no sufficient reason to exempt the present case from this general rule.

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