It held a landowner also owned the strata and minerals, unless they conveyed it, in common law or statute, to someone else, so an oil company making wells 800 to 2,900 feet (240 to 880 m) below the surface was trespass, and had to pay compulsory purchase compensation under the Mines (Working Facilities and Support) Act 1966 s 8(2).

Peter Smith J held that Bocardo's title extended to the substrata beneath the land's surface, and though the pipelines cause not damage, nor affected enjoyment, there was a trespass.

Lord Hope, giving the first and dissenting judgment, said a landowner did own the ground beneath, including minerals, unless there was a conveyance or statute, as in Mitchell [1914] 1 Ch 438.

There had to be a logical limit, where pressure and temperature to the Earth's core made ownership so absurd as to be not worth arguing about, but the wells were not that deep.

… Parliament was at one and the same time extinguishing whatever pre-existing key value Bocardo's land might be thought to have had in the open market and creating a new world in which only the Crown and its licencees had any interest in accessing the oilfield and in which they had been empowered to do so (to turn the key if one wants to persist in the metaphor) compulsorily and thus on terms subject to the Pointe Gourde approach to compensation.Lord Collins agreed with Lord Hope on the principles and Lord Brown on quantum.

‘the correct approach would be to assess a fair and reasonable amount to reflect the key value of the wayleave, in the words of section 8(2), as between a willing grantor and a willing grantee, and to add 10% in accordance with the statute.