Note on horizontal privity
The basic concept of horizontal privity can be express by the aphorism: “If it’s going to run with the land, it must be born with the land,” signifying that a real covenant must, in some sense, be part of the conveyance of the burdened property interest rather than being independent from it. The more restrictive rule requires that the benefited and burdened landowners have a continuing relationship (i.e. a fee simple conveyance from A to B would not satisfy the requirement). So to meet the restrictive rule, a real covenant is unenforceable as such unless the original covenantor and covenantee had a leasehold relationship, or unless their properties were servient and dominant tenements for an easement. The more flexible interpretation permits the horizontal privity requirement to be satisfied if the covenant is part of a conveyance in fee.

Consider five cases:
In case 1, the owner (in fee) of Izzie Haven, B makes a covenant to the owner (in fee) of Bundleofstyx Haven, A, that Izzie and any other pet occupying B will never do anything to make the occupancy of Bundleofstyx Haven undesirable or unsightly or to interfere with any pet residing on Bundleofstyx Haven. A sells Bundleofstyx Haven to C, who sells it to E. B sells Izzie Haven to D, who sells it to F. F’s pet jaguar, “Tizzy,” kills E’s pet coyote, “Barker.” E sues F for breach of the covenant. There is no real covenant to enforce between E and F because A and B lacked horizontal privity.
If, however, in case 2, Izzie Haven was not a separate property parcel but a leasehold on the entire premises of Bundleofstyx Haven, there would be horizontal privity between A and B, even under the English Rule, and the covenant would be enforceable as between E (now the successor to the landlord’s reversion) and F (now the successor to B’s leasehold).
If in case 3, there is no leasehold, but, Bundleofstyx and Izzie Haven are separate but adjacent fee interests, and A had an affirmative easement appurtenant to inspect Izzie Haven for evidence of pet droppings, canine, jaguar or otherwise. Covenant 1 would be enforceable as between E, successor to A’s fee interest, and F, successor to B’s fee interest, under the Massachusetts Rule (the more restrictive American interpretation of horizontal privity) because the easement creates horizontal privity.
Now, in case 4, suppose A subdivides Bundleofstyx Haven, and coveys half in
fee to H, and later, conveys the other half in fee to G. G and H then convey
all of their interests to I and J respectively. When A coveys to H, A insists
that the deed include a covenant promising that H and his heirs or grantees
never use the premises to create or play a song known as “The Conquest Stick.”
J creates such a song and plays it loudly. I sues J for breach of the covenant.
There would be no enforceable real covenant under either the English or the
Finally, in case 5, suppose A subdivides Bundleofstyx Haven, but does not include a covenant in either his conveyance to G or his conveyance to H. H subsequently makes a no-Conquest-Stick-song covenant to G. G and H convey to I and J, as before. Now the covenant is not enforceable as a real covenant between I and J under any interpretation of horizontal privity.
Additional quote notes:
“Horizontal privity takes three forms: the strict English position, the
intermediate
“The intermediate, or
“In
most of the
“In its original English form, it
restricted the use of real covenants to lease transactions. As developed in the
In this American form, the only possible function of the horizontal privity requirement is to insure that covenants appear in recordable instruments. This function is more simply served by the Statute of Frauds and the recording acts. Since the doctrine has little support in modern case law and none among scholars of servitudes law, its elimination should not prove controversial.”[2]
“The term "horizontal privity" refers to a relationship between the original covenantor and covenantee. In order to create a covenant which had the potential to run with the land, the transfer between the parties had to be in the form of a conveyance (in which case, we say that the parties had horizontal privity). The grantor need not have to convey his entire estate to the grantee in order to have horizontal privity, but some portion of an estate had to be transferred. In other words, adjoining landowners could not agree to bind their land for their mutual benefit (no horizontal privity) and have the covenants bind future successors. In addition, at early English common law, covenants could only run with the land when the original parties were in landlord-tenant relationships. Even as late as 1834, in the case of Keppell v. Bailey, the court concluded that horizontal privity was satisfied only by a landlord-tenant relationship.[3]
[1] Susan F. French, Toward a Modern Law of Servitudes: Reweaving the Ancient Strands, 55 S.Cal.L.Rev. 1261, 1292-1293 (1982) [footnotes omitted].
[2] Susan F. French, Servitudes Reform and the New Restatement of Property: Creation Doctrines and Structural Simplification, 73 Cornell L.Rev. 928, 934 (1988) [footnotes omitted]
[3] John W.
Fisher, II, The Evolution of Restrictive Covenants in