Duke Energy International Peru Investments No. 1 Ltd. v. Republic of Peru
ICSID · Investment (ICSID and treaty) · Peru · 18 Aug 2008
Why it matters
This case is a landmark for the scope of tax stabilization clauses in investment treaties and legal stability agreements. It established that a host state's change in interpretation of its own tax laws, even if consistent with the law's text, can breach a stabilization guarantee if it departs from the interpretation prevailing at the time of investment. The award also clarified the limits of estoppel and good faith defenses, emphasizing that approval by non-tax authorities does not bind the tax authority.
Summary
Duke Energy International Peru Investments No. 1 Ltd. (DEI Bermuda), a Bermudan company indirectly owned by Duke Energy, invested in Peru's electricity sector by acquiring shares in Egenor, a Peruvian company, through a privatization process. As part of the investment, DEI Bermuda entered into a Legal Stability Agreement (LSA) with Peru, which guaranteed that certain tax rules would remain stable for a period of time. The LSA included a tax stabilization clause that froze the tax regime applicable at the time of the agreement. After the investment, Peru's tax authority (SUNAT) issued tax assessments against Egenor for two main issues: (1) the depreciation of assets contributed by Duke Energy as a capital contribution, and (2) the tax benefits claimed from a merger between Egenor and another company. SUNAT argued that the depreciation was not allowed because the contribution was a corporate reorganization rather than a capital contribution, and that the merger revaluation did not qualify for tax benefits under the Merger Revaluation Law (MRL). Duke Energy claimed that these assessments violated the tax stabilization guarantee in the LSA, because they changed the interpretation of the tax laws that had been applied at the time of the investment. Duke also argued that Peru had breached the good faith principle (actos propios) because various state agencies, including Electroperú (the state-owned seller), had approved the tax practices. The Tribunal found that Peru had breached the tax stabilization guarantee with respect to the merger revaluation assessment. The Tribunal held that the interpretation of the MRL prevailing at the time of the LSA allowed the tax benefits, and SUNAT's subsequent contrary interpretation constituted a change that violated the stabilization clause. However, the Tribunal rejected Duke's claim regarding the depreciation assessment, finding that the stabilization clause did not cover that issue because the tax treatment was not clearly established at the time. The Tribunal also rejected Peru's estoppel defense, holding that approval by non-tax authorities (like Electroperú) did not create a legitimate expectation that SUNAT would not assess taxes. The Tribunal awarded Duke Energy US$18,444,211 in damages plus interest. The award is significant for clarifying the scope of tax stabilization clauses and the limits of state responsibility for changes in tax interpretation.
The detail
Parties: Duke Energy International Peru Investments No. 1 Ltd. v. Republic of Peru
Case number: ICSID Case No. ARB/03/28
Outcome: The Tribunal found Peru breached the tax stabilization guarantee in the Legal Stability Agreement, awarding Duke Energy US$18,444,211 in damages plus interest.
Quantum: US$18,444,211
Applicable law: Legal Stability Agreement between Peru and DEI Bermuda; Peruvian tax law; ICSID Convention; international law
Issues in play: The dispute involved the collision between Peru's tax stabilization guarantee (freezing tax rules at the time of investment) and subsequent tax assessments by SUNAT (Peru's tax authority) that changed the interpretation of the Merger Revaluation Law (MRL) and depreciation rules.
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