Adverse possession - does applicant have to have known he was not the owner of the land?

My parents bought a house 40 + years ago, when the land was not registered. &#160;I have inherited the property and wish to apply for first registration, but have discovered that a small piece of the garden was not transferred to my parents. &#160;This happened because the conveyance did not include a plan; the property was simply described as the dwelling house and messuage etc known as (address). &#160;It turns out that, when their vendor had bought the property, that conveyance had contained a plan. &#160;This excluded a part of land that my parents believed was within their garden. &#160;Obviously the vendor could not sell them land that he did not own.<br> <br> The land had been bought and sold several times before the vendors bought it, often as part of a larger parcel. &#160;The owner of the excluded section is not known.<br> <br> Given that the original legal firm seems to have provided a sloppy service, I don’t wish to go to them for advice.<br> <br> i would like to apply for adverse possession. &#160;I’m confident we can show that my parents treated the land in question as their own throughout the full time they occupied the house.<br> <br> However, does it matter that my parents apparently did not know that they did not own the land when they were “adversely possessing” it?<br> <br> &#160;

James - the law is a complex one re such claims so whilst I understand the 'sloppy' comment please do seek legal advice if only with regards the specific Q you ask and how you, as their beneficiary, might be able to make a legal claim.&#160;<br> I mention the second point as it reads as if it was your parents who have adversely possessed the land but who are now sadly deceased. And as such that's a much bigger Q to have legally answered than the one you posted.<br> Our PG 5 explains the registration requirements but those come after the legal ones -&#160;<a href="https://www.gov.uk/government/publications/adverse-possession-of-1-unregistered-land-and-2-registered-land/practice-guide-5-adverse-possession-of-1-unregistered-and-2-registered-land-where-a-right-to-be-registered-was-acquired-before-13-october-2003">Practice guide 5: adverse possession of (1) unregistered land and (2) registered land where a right to be registered was acquired before 13 October 2003 - GOV.UK</a>