Arbitration — ICSID Convention — Argentina–United States Bilateral Investment Treaty, 1991 (“BIT”) — Argentina gas industry privatization in 1992 — Foreign investment — Claimants investing in Transportadora de Gas del Sur (“TGS”) — Claimants satisfying requirements of BIT — Tax assessments by Argentine provinces — Claimants instituting arbitration proceedings — Tax matters — Article XII of BIT — Whether stamp taxes on operations of TGS expropriatory and illegal — Whether violating Argentine law — Whether violating international law — Whether violating obligations under BIT — Whether tax measures tantamount to expropriation of investment — New request for arbitration — Claimants alleging certain tariff and other financial measures implemented by Argentina affecting investment and contravening BIT — New request as ancillary claim to original claim — ICSID Convention, Article 46

Jurisdiction — Whether Tribunal having jurisdiction over investors’ claim — Whether investors demonstrating prima facie that adversely affected by Argentina’s tax measures — Whether tax assessments violating rights accorded to foreign investors under BIT — Whether Tribunal having jurisdiction to consider matter under BIT — Matter before Argentine courts — Relevance — Tax assessments by Argentine provinces — Whether Argentina liable — General tax policies and arrangements of Argentina and its provinces — State sovereignty — State responsibility — Article XIII of BIT — State incurring responsibility and liability for unlawful acts of agencies and subdivisions under international law — International Law Commission’s Articles on State Responsibility

Jurisdiction — Original claim — Competence — Admissibility of claims — Applicable provisions — Whether Claimants having status of protected investor — Jus standi — Whether shareholders might claim independently from corporation concerned even if not in majority or in control of company — Definition of investment under Article I(1) of BIT — Indirect damages — Extent of consent to arbitration of host State — Whether excluding tax matters — Whether present dispute arising directly out of investment — Whether Claimants having present interest to bring action under BIT — Whether investment agreement or authorization — Claim for protection under BIT against alleged expropriation representing specific dispute — Powers of Tribunal — Injunctive relief — Whether breach of contractual rights also contravention of treaty rights — Determination at merits phase — Whether conditions for “fork in the road” principle present

Jurisdiction — Ancillary claim — Whether Claimants protected investors under BIT — Jus standi — Definition of investment under Article I(1)(a) of BIT — Whether agreement allowing locally incorporated companies having “foreign control” to accede to ICSID arbitration — ICSID Convention, Article 25(2)(b) — Distinction between treaty-based claims and contract-based claims

Interpretation — ICSID Convention — Article I(1) of BIT — Meaning of “investment” — Vienna Convention on the Law of Treaties, 1969, Article 31 — Literal and purposive construction — NAFTA, Article 1139 — Whether extending to indirect investments — Whether minority and indirect shareholders having independent right of action separate from affected local company — Decisions of ICSID tribunals not binding precedents

Interpretation — ICSID Convention — Article 25(2)(b) — Meaning of “foreign control” — Bilateral investment treaty — Whether precluding Claimant from acceding to ICSID jurisdiction

Interpretation — ICSID Convention and bilateral investment treaty — Investment agreement — Whether share transfer agreement constituting investment agreement — Indemnity clause — Investment constituting various instruments