Sergio Marchisio Discussed The Current Legal Implications Of Due Regard In Outer Space At The IISL/ECSL Symposium

IISL/ECSL Symposium

at UNCOPUOS LSC 2025

DUE REGARD IN OUTER SPACE: CURRENT LEGAL IMPLICATIONS

Introduction by

Sergio Marchisio

Chair ECSL, Sapienza University of Rome

Mr. Chairman, Distinguished Delegates, Director of UNOOSA,

It is a privilege to deliver these opening remarks on behalf of the European Centre for Space Law (ECSL), following those of Kai-Uwe Schrogl, President of the International Institute of Space Law (IISL).

Founded in 1989 under the auspices of the European Space Agency (ESA), the ECSL serves as a platform for fostering dialogue and collaboration among all those engaged in the development and application of space law. Through its educational programmes, initiatives, conferences, and colloquia, the ECSL seeks to advance understanding and stimulate informed debate on the evolving legal frameworks governing outer space.

This year, the Symposium, co-organised annually by the ECSL and the IISL during the Legal Subcommittee of COPUOS, is focused on a particularly timely topic: “Due Regard in Outer Space: Current Legal Implications.”

Let me briefly outline the themes that will guide today’s discussion.

The concept of due regard is fundamental to fostering coordination and cooperation among States as outer space activities grow in scope, number, and complexity. Yet, its meaning and practical application remain underdeveloped. Consequently, clarifying the substance and scope of this obligation is more urgent than ever.

To that end, we must examine the legal, procedural, and operational elements that give effect to the principle of due regard – what it requires, when it is triggered, and how it can be implemented in practice.

It is worth recalling that the notion of due regard was absent from the 1962 Draft Declaration submitted by the USSR. Its first formal appearance was in Principle 1 of the UK’s Draft Declaration on Legal Principles. Article IX of the Outer Space Treaty later refined and expanded this concept – most notably by shifting the focus from strictly defined rights to broader interests. This marked a deliberate and meaningful evolution. In this context, due regard extends beyond legal entitlements narrowly defined; it encompasses legitimate interests that, while not necessarily codified in binding law, are nonetheless recognized within the international legal order, particularly where the exercise of freedom is concerned.

The principle is essential to ensuring the peaceful coexistence of diverse, yet equally legitimate activities conducted in the same areas of outer space or on celestial bodies. An early interpretation of Article IX was offered in 1967 by NASA legal scholars Paul G. Dembling and Daniel M. Arons. They observed that Article IX is anchored in the principles of international cooperation and due regard, and that its subsequent provisions operationalize these values. Their interpretation remains relevant: the principle is reflected in

the obligation to avoid harmful contamination of outer space and adverse effects on Earth’s environment;
the duty to engage in international consultations;
the requirement for States planning potentially harmful activities to consult with others; and
the right of States to request consultations regarding such activities.

To this framework, we must now add the essential dimension of information sharing. Though not explicitly mentioned in Article IX, transparency and the exchange of information are indispensable to the meaningful implementation of the due regard obligation.

Importantly, the obligation to show due regard is not absolute; it is context-dependent. Its application varies according to factors such as the nature and significance of the activities involved, the potential degree of interference, and the availability of alternative means to achieve the same objectives.

Today’s panel will examine these dimensions from multiple perspectives: how to make the principle of due regard operational in practice; how it intersects with Japan’s guidelines on collision avoidance; the rising importance of space traffic coordination; and the legal infrastructure needed to support peaceful, safe, and sustainable lunar exploration.

We will also hear regional perspectives from emerging spacefaring nations in Latin America and Africa, as well as reflections on the principle’s implications for intergenerational equity and the rights of future generations.

With that, let us now turn to our distinguished panel of speakers.

Symposium’s conclusions

I think that we can conclude this remarkable event by underlining that the topic that we have addressed is of outstanding relevance for the future of outer space activities. The Symposium highlighted a growing consensus on two main points.

First, that the principle of due regard is fundamental to fostering coordination and cooperation among States as outer space activities grow in scope, number, and complexity. Yet, its meaning and practical application remain underdeveloped. Consequently, clarifying the substance and scope of this obligation is more urgent than ever.

From that the second takeaway is that the “due regard” principle must evolve from abstract obligation to actionable norm. Continued dialogue among legal scholars, policymakers, and industry, as well as members of the Legal Subcommittee, on this topic is essential to shape a cooperative and sustainable space future.

Our symposium has been one important step in that direction. This is why I thanks all the speakers for sharing with the Subcommittee members their thoughts and ideas.

At the same time, I thank the president of IISL and the Director of UNOOSA for their engaged participation. Kai-Uwe the floor is yours.