An easement by necessity is implied by law, not created by any written grant, when a parcel becomes landlocked as a result of a division of previously commonly owned land, leaving it with no legal access to a public road except across the retained or conveyed portion. Courts imply the easement on the theory that the original grantor and grantee could not have intended to render a parcel unusable, so the law supplies the access right the parties presumably would have provided.

The claimant must generally show unity of prior ownership followed by severance that created the landlocked condition, and true necessity, not mere convenience, meaning no other legal access exists or existed at the time of severance. Disputes commonly involve the location and scope of the easement once necessity is established (courts typically choose the route least burdensome to the servient estate), whether the necessity has since ended (for example, if a new public road was later built), and whether an alternative, even if inconvenient or costly, defeats strict necessity.

Juricratic treats the 'unity of title and severance' element as a largely binary, record-based fact pulled from the chain of title, while treating 'necessity' and 'reasonable route location' as contestable dials, since those are the two elements most often actually litigated once common ownership history is established.

Landlocked-parcel owners and their counsel trace the chain of title to establish prior common ownership and the moment of severance, then litigate the scope and precise routing of the implied easement, while burdened neighboring owners push for the narrowest possible route and argue any available alternative access defeats strict necessity.