In the age of Big Data and machine learning, with its ever-expanding possibilities for data mining, the question of who is entitled to control the data and benefit from insights that can be derived from them matters greatly for the shape of the future economy. Therefore, this topic should be assessed under the heading of distributive justice. There are different views on who is entitled to control data, often driven by analogies between claims to data and claims to other kinds of things that are already better understood. This chapter clarifies the value of approaching the subject of control over data in terms of (a notion of moral, rather than legal) ownership. Next, drawing on the work of seventeenth-century political theorist Hugo Grotius on the freedom of the seas, and thus on possibilities of owning the high seas, I develop an account of collective ownership of collectively generated data patterns and explore several important objections. Since control over data matters enormously and is poorly understood, we should treat questions about it as genuinely open. This is a good time to bring to bear unorthodox thinking on the matter.

The laws of war, as expounded by Grotius, resulted from an interplay of natural law and the voluntary law (or law of nations), which was a customary law based on state practice.Important ways in which the voluntary law departed from natural law were in according equal rights to belligerents in war, without regard to the justices of the respective causes.The predominant principle governing the conduct of war was necessity, which had both a permissive and a restrictive character.Grotius was a firm supporter of moderation in the exercise of the rights of belligerency.This worked particularly to the benefit of civilians and prisoners of war.He insisted that principles of good faith must operate in war, so that perfidious acts were prohibited, though ordinary ruses of war were allowed.The voluntary law, to Grotius, allowed the unlimited taking of property belonging to enemy nationals.Grotius also gave careful attention to modern concerns such as targeted killing.An important contributions was to lay the groundwork for the law of neutrality, setting out rules on the treatment of neutral-owned property in war and on the treatment of enemy-owned property in the custody of neutrals.

Grotius’s theory of property was meant to yield practical results. The principle of the freedom of the seas, for instance, was based on the idea of seizure as a constituent element of property and exclusivity. This focus on practical results enables a secularized reading of his theory of property. However, some essential aspects of his property theory are not entirely comprehensible without taking into account Grotius’s wider theological framework. Therefore, in this article I will focus on Grotius’s idea of consent to the principle of first occupation as the foundation of his property theory, and link it with his theologically loaded conceptions of man’s freedom and equality, or the universal fellowship of humankind.