Ofcom operates the Sitefinder database of mobile phone mast locations, much of which is published and searchable online. Users can, for example, search for masts by address or postcode or view them on a map.
The database, though, contains detailed information that is not searchable. Some of it appears on the map when a user points at a site, and some of it is not made publicly available at all.
Ian Henton, the information manager for NHS body Health Protection Scotland, made a request under the Freedom of Information (FOI) Act for all the information held by Ofcom to be made public and to be searchable.
The Information Commissioner ruled in Henton's favour, as did the Information Tribunal when Ofcom appealed. The regulator appealed to the High Court, which has also now ruled that the data must be published.
The full judgment is not yet available but a spokeswoman for the Information Commissioner's Office (ICO) confirmed that the Court upheld the original ruling of the ICO.
Ofcom had argued in the Information Commissioner and Information Tribunal hearings that the site would no longer be useful if it had to publish all the required information because the industry would withdraw co-operation from the project. It said that operators had already withdrawn their co-operation.
Since that withdrawal of co-operation last autumn, though, all operators apart from T-Mobile have provided voluntary updates to the information in the database.
The publication of the full, searchable database would be commercially damaging, operators said. They said, for example, that it would allow a user to plot an operator's entire network.
Ofcom did not say whether or not it intends to appeal the ruling further.