As adjusted by the Land Titles Act, discussed below, a prescriptive easement may be established in two ways under the Real Property Limitations Act, and a third way pursuant to what is known as the doctrine of lost modern grant. At common law, prescription was based on the legal fiction that if there were 20 years of uninterrupted use by the owner of the dominant tenement, it could be presumed that there had been a grant of an easement and that the grant had been lost.
 The relevant provisions of the Real Property Limitation Act are set out below:
- No claim that may be made lawfully at the common law, by custom, prescription or grant, to any way or other easement, or to any water course, or the use of any water to be enjoyed, or derived upon, over or from any land or water of the Crown or being the property of any person, when the way or other matter as herein last before-mentioned has been actually enjoyed by any person claiming right thereto without interruption for the full period of twenty years shall be defeated or destroyed by showing only that the way or other matter was first enjoyed at any time prior to the period of twenty years, but, nevertheless the claim may be defeated in any other way by which it is now liable to be defeated, and where the way or other matter as herein last before-mentioned has been so enjoyed for the full period of forty years, the right thereto shall be deemed absolute and indefeasible, unless it appears that it was enjoyed by some consent or agreement expressly given or made for that purpose by deed or writing.
- Each of the respective periods of years mentioned in sections 30 and 31 shall be deemed and taken to be the period next before some action wherein the claim or matter to which such period relates was or is brought into question, and no act or other matter shall be deemed an interruption within the meaning of those sections, unless the same has been submitted to or acquiesced in for one year after the person interrupted has had notice thereof, and of the person making or authorizing the same to be made.
 Section 31 of the Real Property Limitations Act sets a 20-year period or a 40-year period for the creation of prescriptive easements. The period of alleged prescriptive use is specified to be the period immediately before the commencement of an action. For an easement created by the doctrine of lost modern grant, the duration of use does not have to be a 20-year or 40-year period immediately preceding the bringing of an action. The doctrine of lost modern grant establishes that where there has been 20 years of uninterrupted enjoyment of an easement and such enjoyment has all the necessary qualities to fulfill the requirements of prescription, the law will adopt the legal fiction that such a grant was made. The nature of the enjoyment of the land necessary to establish an easement under the doctrine of lost modern grant is exactly the same as that required to establish an easement by prescription under a statute of limitations.
 To establish a prescriptive easement, the claimant must demonstrate a continuous, uninterrupted, open and peaceful use of the land, without objection by the owner. To acquire an easement by prescription under a statute of limitations or under the doctrine of lost modern grant, the claimant’s use of the land must be “as of right” or, as described in the old authorities, “nec vi, nec clam, nec precario”—“without violence, without stealth (secrecy), without permission”.
 To say that the use of the easement must be “as of right,” is to say that the enjoyment of the easement is not just permissive (i.e., not just a licence) and the owner of the dominant tenement must actually manifest an ownership right; i.e., an entitlement to use the easement. A claimant may rely on the use of predecessor owners to make up the requisite period of “as of right” use.
 During the 20-year period under the Real Property Limitations Act or pursuant to the doctrine of lost modern grant, the owner of the servient tenement’s oral or written consent or permission defeats any claim for a prescriptive easement. During the 40-year period under the Real Property Limitations Act, a written but not an oral consent will defeat any claim for a prescriptive easement.
 The Ontario Law Reform Commission Report on Limitation of Actions stated that “as of right” means that the claimant must show that he or she enjoyed the easement “as if entitled to it.” In the English case of De La Warr v. Miles, Brett, L.J. said that “as of right” meant “that he who asserts a prescriptive right claims as having a right to do it without the Lord’s permission, and that he has so done it without that permission.” The Ontario Law Reform Commission in its report, states at p. 143:
The person claiming the easement must show that the owner of the land has acquiesced in his enjoyment. The latter must have acquiesced yet not given permission. It is not easy to tell whether or not there was, in fact, acquiescence in a particular case.
 The theory behind a claim for an easement based on prescription under a limitations statute or under the doctrine of lost grant is that the evidence establishes that the owner of the servient tenement has with knowledge consented or acquiesced to the establishment of an incorporeal ownership interest in land by the owner of the dominant tenement as opposed to licensing the use of the land without conferring an ownership interest in it. Use by permission or licence is insufficient for establishing a prescriptive easement. The theory was explained in Sturges v. Bridgman by Thesiger, LJ. as follows:
Consent or acquiescence of the owner of the servient tenement lies at the root of prescription, and of the fiction of a lost grant, and hence the acts or user, which go to the proof of either the one or the other, must be, in the language of the civil law, nec vi nec clam nec precario; for a man cannot, as a general rule, be said to consent to or acquiesce in the acquisition by his neighbour of an easement through an enjoyment of which he has no knowledge, actual or constructive, or which he contests and endeavours to interrupt, or which he temporarily licenses.
 The threshold for meeting the criteria for establishing a prescriptive easement under the Limitations Act or by lost modern grant is high, and courts are hesitant to recognize an easement by prescription because doing so would permit a landowner’s neighbourly accommodation of sufferance to ripen into a legal burden on his or her lands without compensations. Use permitted by neighbourliness and enjoyed on that basis is insufficient to establish an easement by prescription.