Concerning the applicability of existing law, the Tribunal held that it was wrong to conclude that the BITs had no rights to the host state and did not impose any obligations on investors.

In the Tribunal's view, the applicable BIT is not an isolated or closed system, as the BIT itself allows other sources of international law to be referred to.

The Tribunal concluded by looking at the three rules of the BIT:
The MFN clause entitled Dispute Resolution Rules, Applicable Law Rule, and “Most Favourable Terms”. It noted that the applicable rule of law is particularly interesting because it refers to “general principles of international law.”

The Tribunal found that the reference was meaningless if BIT was to isolate other areas of international law. According to the Tribunal, even interpreting the BIT as such would be wrong because the interpretation of a contract must give an effective application to its terms. The Tribunal found, therefore, that the BIT cannot be regarded as an isolated rule of international law for “the sole purpose of protecting investments through rights granted exclusively to investors.”

The Tribunal turned to the question of BIT's involvement with international human rights law. Here, it rejects claimants' claim that a state cannot be subject to international law in the state system, and that “such a policy, despite its significance in the past, has lost its impact and relevance. Such terms and conditions apply to individuals.”

Interestingly, even if a BIT treats investors as subjects of international law, it does not undermine the notion that foreign investors may be subject to international legal obligations. Moreover, in light of the recent developments in international law, the Tribunal has asserted that it is no longer acceptable that internationally-run corporations are exempt from becoming subjects of international law.

To determine whether international legal obligations exist with non-state entities, the Tribunal ruled that:
“the specific functions of the corporation are related to human rights”.

In doing so, the Tribunal looked at international conferences and referred to the Universal Declaration of Human Rights (UDHR), the International Covenant on Economic, Social and Cultural Rights (ICESCR) and the International Labour Organization's Declaration on Multinational Organizations and Social Policy Principles. These tools describe human rights that may or may not be related to water rights.

The Tribunal has found that Article 30 of the UDHR and Article 5 (1) of the ICESCR are relevant in the present context. These articles include:

Article 30 UDHR
‘Nothing in this Declaration refers to any right of any State, group or person to engage in any activity or to perform any act intended to destroy the rights and freedoms set forth herein.’

Article 5 (1) ICESCR
‘Nothing in the present Agreement implies any right to any State, Group or Person to engage in any activity or to do anything that is intended to destroy the rights or freedoms recognized herein, or is not within their limits. Rather than as provided for in the present Agreement.’

The Tribunal asserted that the right to water and sanitation is undeniable as part of human rights and that States must provide safe and clean drinking water and sewerage to all people subject to this authority. Services. Despite this finding, the remaining challenge of the Tribunal is to establish a legal obligation on the investor, but it does not find such a duty.

According to the Tribunal, the Argentine argument involved the concessionaire's obligation to enforce the human right to water for water and wastewater, and this means that the source of the human rights in question is not BIT or international law, but the concession agreement.

In conclusion, the Tribunal examined the human rights to water rights in the AGBA's concession structure. It agreed with Argentina that the offer was designed to contribute significantly to the enforcement of the people's water rights. Even so, it found that there was no such obligation under international law. The major responsibility is to exercise its power over concessions to ensure and protect the basic right of the people to water and sanitation.