Mr. Billy Hawkes:

They are personal data which have been made less personal by removing some of the identifying points. There are various levels of pseudonymisation. Again, it is a discussion point as to whether we can have totally anonymous data. Given the amount of data available on us in the world, people have proved that something we might think is totally anonymous can, in fact, be linked with an individual. Pseudonymous data are somewhere between anonymous, where they cannot be linked with a person, and personal, which can definitely be linked with a person. Again, it is a whole can of worms on its own.