G.R. No. 104151 - Commissioner of Internal Revenue vs. Court of Appeals

Case Summary (G.R. No. 104151)

Key Dates and Procedural Posture

Relevant assessment notices were served on ACMDC on April 9, 1980 (1975 deficiencies) and September 23, 1980 (1976 deficiencies). ACMDC protested and filed petitions in the Court of Tax Appeals (consolidated as CTA Cases Nos. 3467 and 3825). The CTA rendered a consolidated decision on May 31, 1991. The parties appealed to the Court of Appeals, which issued judgments on February 12, 1992 (CA-G.R. SP No. 25945) and May 22, 1992 (CA-G.R. SP No. 26087). The present matters were consolidated for Supreme Court review by resolution of September 1, 1993. The applicable constitutional framework for the decision is the 1987 Philippine Constitution.

Applicable Law and Statutory Provisions

Key provisions of the National Internal Revenue Code (as then in force) discussed in the decision include Section 243 (ad valorem tax on output of mineral lands not covered by lease), Section 246 (definitions of "gross output," "minerals," and "mineral products" and the rule against deductions except for C.I.F. freight and insurance), Section 245 (time and manner of payment of royalties and ad valorem taxes and surcharge provisions), Section 186 (percentage tax on sales of other articles — manufacturer’s sales tax), Section 191 (contractor’s tax provisions, including lessors of personal property), and Section 194(x) (definition of "manufacturer").

Facts: Extraction, Processing, and Sales Mechanism

ACMDC extracted copper ore which underwent physical milling and concentration at Toledo into copper concentrate (28–31% copper). The concentrate was shipped to Mitsubishi Metal Corporation mills in Japan where smelting, electrolytic refining, and fabrication produced copper cathodes and further fabricated wire bar (the manufactured copper). ACMDC used the London Metal Exchange (LME) quotation for copper wire bar as the reference in pricing because no global market quotation for copper concentrate existed. Smelting and refining charges were incurred in Japan between shipment of concentrate and production of the finished wire bar.

Tax Assessments and Administrative Proceedings

On the BIR examiners’ report, the Commissioner assessed ACMDC for alleged deficiency ad valorem percentage and fixed taxes for 1975 (P12,391,070.51) and 1976 (P13,531,466.80, plus P5,000 compromise penalty). ACMDC’s protests were denied and it filed petitions in the CTA. The CTA consolidated the cases and, on May 31, 1991, held that ACMDC was not liable for the large ad valorem deficiency amounts on copper and silver for 1975 and 1976 because ACMDC’s method—using the LME wire bar price less freight, insurance, and smelting/refining charges—appropriately approximated the market value of copper concentrate. The CTA nonetheless held ACMDC liable for P1,572,637.48 composed of multiple 25% surcharges for late payment/late filing on ad valorem tax for precious metals and pyrite, alleged deficiency manufacturer’s sales tax and surcharge (1975), and contractor’s tax and surcharge (1975 and 1976), plus interest where applicable.

Court of Appeals Decisions and Issues on Appeal

The Commissioner appealed the deletion of ad valorem tax liability (arguing deductions for smelting and refining were impermissible under Section 246, which allows only freight and insurance deductions for C.I.F. sales). ACMDC appealed the CTA’s imposition of the P1,572,637.48 liability. The Court of Appeals (CA) affirmed the CTA on the computation of ad valorem tax (February 12, 1992) and later modified the CTA judgment (May 22, 1992) by deleting certain surcharge awards related to specified extraction periods, further reducing ACMDC’s liability. The Commissioner and ACMDC separately sought Supreme Court review.

Issue Presented in G.R. No. 104151 (Commissioner’s Petition)

The sole issue framed by the Commissioner: whether refining and smelting charges should be deducted in computing the ad valorem tax on copper when ACMDC used the LME price of manufactured copper as the reference for the market value of copper concentrate.

Legal Analysis on the Ad Valorem Tax Base

Statutory framework: Section 243 imposes a 2% ad valorem tax (1.5% for gold) on the actual market value of annual gross output of minerals or mineral products (not covered by lease). Section 246 defines "gross output" as the actual market value "without any deduction from mining, milling, refining, transporting, handling, marketing, or any other expenses" but provides a narrow exception: where minerals are sold or consigned abroad under C.I.F. terms, actual ocean freight and insurance may be deducted.

Court’s reasoning: The Court recognized the general statutory rule that the ad valorem tax should be computed on the actual market value of the mineral product in its condition at removal from the mine, without deductions for post‑extraction processing. Precedents (e.g., Cebu Portland Cement Co. and Republic Cement) establish that the ad valorem tax is a severance tax measured by the market value of the mineral product before it undergoes chemical or manufacturing processes that substantially change it into a finished product.

Application to facts: ACMDC’s mined and removed product was copper concentrate (a product of physical milling/concentration), not the finished copper wire bar which underwent chemical/manufacturing processes (smelting, electrolytic refining, fabrication) in Japan. Because there was no available market quotation for copper concentrate, ACMDC used the LME price for copper wire bar as a reference point. In order to estimate the actual market value of copper concentrate at removal, ACMDC—and the CTA and CA—deducted the charges incurred after shipment (smelting, electrolytic refining, fabrication) from the LME wire bar price. This deduction was not treated as a deduction from the concentrate’s value per se under Section 246, but rather as a method to approximate the market value of the mineral product at the time of removal when no direct market quotation for the concentrate existed.

Conclusion on issue: The Court found that allowing the deduction of smelting and refining charges from the LME wire bar price to approximate the market value of copper concentrate was not contrary to Section 246. The principle is that the ad valorem tax must be based on the market value of the mineral in its condition at removal; when a finished product’s price is used as a proxy due to absence of concentrate quotations, post‑removal manufacturing costs must be subtracted to approximate the concentrate’s market value. The Supreme Court therefore affirmed the CA and CTA conclusions on the method of computing the ad valorem tax for copper concentrates.

Commissioner’s Argument about Administrative Consistency and Hilado

The Commissioner contended that a different construction should be applied despite previous CTA decisions relied upon by ACMDC. The Court rejected the Commissioner’s attempt to depart from a well‑reasoned CTA decision, noting (1) the CTA is a judicial tribunal specialized in tax matters and its decisions have persuasive effect; and (2) the Supreme Court will not disturb the considered conclusion of such a tribunal absent an abuse of authority. The Hilado doctrine (involving prior rulings by Commissioners) was distinguished because the CTA is not merely an administrative superior but a judicial body.

Issues Presented in G.R. No. 105563 (ACMDC’s Petition)

The petition presented three issues: (A) liability for the 25% surcharge for late filing/late payment of ad valorem tax on silver, gold and pyrite (1976); (B) liability for manufacturer’s sales tax and surcharge (1975) and interest on grinding steel balls supplied to a competitor; and (C) liability for contractor’s tax and surcharge on alleged leasing of personal property (1975 and 1976) plus interest.

Surcharge on Silver, Gold, and Pyrite (Section 245)

Statutory rule: Section 245 requires ad valorem taxes to be due and payable upon removal and mandates quarterly sworn returns with payment within twenty days after quarter close; a 25% surcharge is added for late payment (50% where false or fraudulent returns are made). Bad faith is not a prerequisite for the 25% surcharge.

Application and findings: ACMDC argued that quantities of silver and gold could only be determined after smelting and refining in Japan and that pyrite was not removed from the mine site. The CTA and the Supreme Court found these defenses insufficient. Testimony from ACMDC’s own witness established that laboratory assays in the Philippines provided percentage or gram‑per‑dmt estimates for copper, gold and silver and that assay results were used as the basis for ad valorem tax payment. Thus estimated commercial quantities of silver and gold could have been determined and provisional payment made. Regarding pyrite, ACMDC was estopped (estoppel in pais) from contesting removal because it had previously declared and paid ad valorem tax on pyrite for the same year, and evidence showed shipments of pyrite outside the mine site to parties other than ACMDC’s sister company. The 25% surcharge for late payment therefore correctly applied and was mandatory; the Commissioner had no authority to waive it.

Manufacturer’s Sales Tax (Section 186) and Definition of Manufacturer (Section 194(x))

Statutory rule and tax character: Section 186 imposed a 7% percentage tax on original sales by manufacturers; Section 194(x) defines "manufacturer" to include persons who alter raw materials by physical or chemical process and who produce finished products "for the purpose of their sale or distribution to others and not for his own use or consumption." Title V provisions (including Sections 186 and 191) are pri

Case Syllabus (G.R. No. 104151)

Procedural posture and consolidation

Two petitions for review on certiorari were filed separately: G.R. No. 104151 by the Commissioner of Internal Revenue and G.R. No. 105563 by Atlas Consolidated Mining and Development Corporation (ACMDC).
The petitions sought reversal and setting aside of Court of Appeals judgments in CA-G.R. SP No. 25945 (promulgated February 12, 1992) and CA-G.R. SP No. 26087 (promulgated May 22, 1992), respectively.
Both matters originated from consolidated Court of Tax Appeals cases (C.T.A. Cases Nos. 3467 and 3825) arising from assessments for taxable years 1975 and 1976.
The petitions were consolidated by this Court in a resolution dated September 1, 1993; the consolidated matters were decided by the Supreme Court (Regalado, J., delivering the decision) on March 10, 1995.
The Court of Appeals (two separate divisions) had issued rulings affecting different portions of the tax court's judgment; the parties sought further review before the Supreme Court.

Factual background

Atlas Consolidated Mining and Development Corporation (ACMDC) is a domestic corporation operating a mining concession in Toledo City, Cebu, exporting its products to Japan and other foreign countries.
On April 9, 1980, the Commissioner served ACMDC with an assessment notice and demand for P12,391,070.51 representing deficiency ad valorem percentage and fixed taxes, including increments, for taxable year 1975 (based on a BIR examiners' report).
On September 23, 1980, another assessment notice was served against ACMDC for P13,531,466.80 representing deficiency ad valorem and business taxes for 1976, plus a P5,000 compromise penalty (based on another BIR examiner's report).
ACMDC protested both assessments; the protests were denied and ACMDC filed petitions in the Court of Tax Appeals (C.T.A. Cases Nos. 3467 and 3825), which were consolidated because they were substantially identical except for periods and amounts.
The Court of Tax Appeals (May 31, 1991) rendered a consolidated decision that:
- Deleted or sustained ACMDC's theory removing ad valorem tax liability on copper and silver for 1975 and 1976 in the respective amounts of P11,276,540.79 and P12,882,760.80 by allowing deduction of refining and smelting charges (in addition to freight and insurance) from the London Metal Exchange (LME) price of manufactured copper.
- Imposed liability on ACMDC for a reduced amount totaling P1,572,637.48 (exclusive of interest) consisting of 25% surcharges for late payment/late filing of notice of removal on silver, gold, and pyrite for certain periods, and alleged deficiency manufacturer’s sales tax and contractor’s tax.
The dispositive portion of the C.T.A. judgment ordered ACMDC to pay, inter alia:
- P297,900.39 as 25% surcharge on silver (Nov. 1, 1974–Dec. 31, 1975);
- P161,027.53 as 25% surcharge on silver for 1976;
- P315,027.30 as 25% surcharge on gold (Nov. 1, 1974–Dec. 31, 1975);
- P260,180.55 as 25% surcharge on gold for 1976;
- P53,585.30 as 25% surcharge on pyrite (Nov. 1, 1974–Dec. 31, 1975);
- P53,283.69 as 25% surcharge on pyrite for 1976;
- P316,117.53 as deficiency manufacturer’s sales tax and surcharge for 1975 plus 14% interest from January 21, 1976 until paid (P.D. No. 69, Sec. 183);
- P23,631.44 as deficiency contractor’s tax and surcharge on lease of personal property for 1975 plus 14% interest from January 21, 1976;
- P91,883.75 as deficiency contractor’s tax and surcharge on lease of personal property for 1976 plus 14% interest from April 21, 1976.
The Commissioner appealed to the Court of Appeals (docketed CA-G.R. SP No. 25945) contesting deletion of the ad valorem tax on copper and silver; ACMDC appealed to the Court of Appeals (docketed CA-G.R. SP No. 26087) contesting the imposition of the P1,572,637.48 liability.
The Court of Appeals (Feb. 12, 1992 in CA-G.R. SP No. 25945) dismissed the Commissioner's petition and affirmed the tax court’s manner of computing the ad valorem tax (i.e., allowing deduction of smelting/refining).
The Court of Appeals (May 22, 1992 in CA-G.R. SP No. 26087) modified the tax court decision by deleting certain surcharge awards for the period Nov. 1, 1974 to Dec. 31, 1975 (removing three specified items) and thereby reduced ACMDC’s tax liability to P906,124.49.

Issues presented to the Supreme Court

G.R. No. 104151 (Commissioner): Whether, in computing the ad valorem tax on copper, charges for smelting and refining should be deducted, in addition to freight and insurance costs, from the price of copper concentrates.
G.R. No. 105563 (ACMDC): Three issues presented:
- (A) Whether ACMDC is liable for a 25% surcharge for alleged late filing of notice of removal / late payment of the ad valorem tax on silver, gold and pyrite extracted during taxable year 1976.
- (B) Whether ACMDC is liable for payment of manufacturer’s sales tax and surcharge for taxable year 1975, plus interest, on grinding steel balls borrowed by a competitor.
- (C) Whether ACMDC is liable for payment of contractor’s tax and surcharge on alleged lease of personal property during taxable years 1975 and 1976 plus interest.

Relevant statutory provisions quoted and applied

National Internal Revenue Code provisions at issue (as in source):
- Sec. 243 — imposes ad valorem tax (2% of output value; gold 1½%) on actual market value of annual gross output of minerals/mineral products from mineral lands not covered by lease; requires notice before removal.
- Sec. 246 — defines "gross output" as the actual market value of minerals/mineral products or bullion from each mine or mineral lands operated as a separate entity without any deduction from mining, milling, refining, transporting, handling, marketing, or any other expenses; proviso allows deduction of actual cost of ocean freight and insurance if sold/consigned abroad under C.I.F. terms; definitions of "minerals" and "mineral products"; distribution of royalties and taxes.
- Sec. 245 — prescribes time and manner of payment: ad valorem taxes due upon removal; bond option for removal without prepayment; returns required quarterly and payment within twenty days after quarter close; 25% surcharge if taxes not paid within prescribed period; 50% surcharge if false or fraudulent return.
- Sec. 194(x) — definition of "manufacturer" (includes persons who by physical or chemical process alter raw materials to prepare for special uses or reduce to marketable shape, and who produce such finished products for sale/distribution and not for own use).
- Sec. 186 — percentage tax on sales of other articles: 7% on every original sale, barter, exchange intended to transfer ownership, to be paid by manufacturer; deductible cost of materials similarly taxed.
- Sec. 191 (paragraph 17) — contractor’s tax: lessors of personal property subject to contractor’s tax of 3% of gross receipts.
The Court repeatedly invoked the legal characterization of the ad valorem tax as a severance tax (a charge upon the privilege of severing or extracting minerals) and the principle that ad valorem tax is to be computed on the market value of the mineral in its condition at time of removal, before substantial chemical/manufacturing change.

Lower courts’ reasoning on ad valorem tax base and deductions

The tax court and subsequently the Court of Appeals accepted ACMDC’s approach of using the London Metal Exchange (LME) price on wire bar (manufactured copper) as a reference point because no market quotation for copper concentrates was locally or internationally available.
Because the selected reference was the price of a manufactured copper product (copper wire bar), the tax court allowed deduction from that LME price of charges and costs incurred after shipment from Toledo to the time of manufacture into wire bar (namely, smelting, electrolytic refining and fabricating), such that the net remainder reasonably approximated the market value of copper concentrate at the mine (C