1. English does not allow to acquire by presciption the title to land itself.

2. But incorporeal rights (easements etc.), which do not carry with them the right to possession, can be acquired by pres- cription.

3. Who is in possession of something 'corporeal', such as land, is protected against anyone except a person with a better right to possession than his. (If 'squatter' A is evicted by 'squatter' B, A has an actiohn to oust B although A himself may be evicted by the rightful owner of the land.)

4. But a possessor might even have a defence against an action by the owner, after the requisite period of limitation has run in respect of an action against him: his possession will have become 'ripened' by lapse of time into ownership.
The period is 12 years (Limitation Act 1980). It applies to owner of legal estates as well as owners of equitable interests. Once the time's up, the owner's right to sue is lost, and his title itself is destroyed.

5. The provisions regarding fraud and mistake apply as well.