According to the court opinion[0]:
It is for all these reasons that anything in the contractual documents between Jagex
and the players, or in the civil law more generally, which would preclude the player
having any enforceable private law personal property rights in the gold pieces, is not
determinative as to whether they are property for the purposes of the definitions in the
Theft Act.
The court draws a comparison to precedent where drug dealers stole illegal drugs from other drug dealers, which were also found to be "property" as defined by the Theft Act[1]: It was confirmed in R v Smith (Michaael Andrew) [2011] EWCA Crim 66 that illegally held
Class A drugs are property within the meaning of the Theft Act and are capable of being
stolen. A theft or robbery amongst rival drug gangs can be indicted as such, because the
criminal law is concerned with the public order consequences of preventing such behaviour,
notwithstanding that it would be contrary to public policy to recognise any property
rights for the purposes of civil enforcement between drug dealers.
The court then approvingly quotes another judge, who in turn quotes Smith's Law of Theft, 9th ed.: "[...] The criminal law is concerned with keeping the Queen’s peace, not vindicating
individual property rights." That observation articulates the principle to be applied in
the present appeal.
So, by that logic, if gamers start doling out murderous retribution against Ubisoft execs for "stealing" their in-game hats, the fact that the gamers have no enforceable property rights in those hats is irrelevant, and the responsible executive(s) could be found criminally liable under the Theft Act because "stealing" gamers' in-game hats threatens the King's peace.[0]: https://caselaw.nationalarchives.gov.uk/ewca/crim/2026/4/dat..., p. 14
[1]: Ibid., p. 13