Whether the land has been developed is a question of fact.
‘Development’ for this purpose is not defined but is interpreted to mean any change from the lands position at purchase. This could include obtaining planning permission.
When considering if obtaining planning permission is sufficient for a main purpose to be developing UK land, all of the facts of the case will need to be considered.
A farmer has decided to sell one of his fields, he realises it will be worth more if it has planning permission so obtains planning permission prior to sale. In this instance it is unlikely a main purpose is developing UK land.
A company carried out research and decided to purchase a plot of land as they have identified the land will be worth significantly more with planning permission. After acquisition they obtain this planning permission and sell the land. In this instance it is likely a main purpose is developing UK land.