Conditional or consentable boundary lines are often referred to in deed descriptions. They have been variously described as a rule of repose for quieting title along a boundary line or as a mechanism to reduce “confusing and vexatious litigation.” But how do such lines actually come to exist? As is often the case with questions regarding legal issues, the best short answer is “it depends.”

While occasional references to conditional, consentable or compromise lines are found in case law from Arkansas, Alabama, Missouri, North Carolina and Virginia, the two states where the vast majority of opinions concerning consentable and conditional lines occur are Pennsylvania and Kentucky. It should be noted at the outset that while many of the principles discussed here are similar to those found in case law from other states, the opinions that follow are state specific.

A rather concise statement from a recent Kentucky case manages to encapsulate the definition, justification and potential problems involved with conditional line agreements in one short paragraph:

“Stake patents,” being as imprecise as they were, led to the use of “conditional line agreements” between adjoining neighbors, so as to avoid the inconvenience and expense of boundary line litigation. “A conditional line in eastern Kentucky is a line made by agreement of [the] parties, generally without the aid of a surveyor.” … Problematically, “conditional line agreements” were often unrecorded, yet marked and known on the ground by their creators-- and just sometimes, their heirs. [cites omitted] 1

The final sentence of this quotation highlights one problem that often occurs when dealing with conditional lines (or with any form of informal boundary line agreement)--future purchasers of the land may not have constructive notice of an informal agreement, particularly where no written record exists. The purchasers might reasonably assume the words describing the original patent still control the location of the property boundaries.

Kentucky common law has developed four requirements that must be fulfilled before a conditional line may be considered the true boundary; these requirements seem to have remained remarkably stable throughout the history of that state.

In order for an agreed or conditional boundary line to be sustained in law, it must be shown that: (1) there was a bona fide controversy between the owners at the time respecting the true location; (2) the line claimed to have been agreed upon was marked; (3) actual possession was taken in accordance with such agreement; or (4) there was continuing acquiescence or mutual recognition by coterminous landowners for a considerable length of time.2

A much earlier Kentucky case indicated the time period required for the recognition of the line by the landowners mirrored the 15-year requirement previously established by the statutory requirement for adverse possession in that state.3 The four elements in this checklist are reminiscent of those requirements whereby a parol agreement may be considered legitimate in many states: initial uncertainty as to the location of the boundary line in question followed by the marking of the uncertain boundary supported by evidence of subsequent agreement or acquiescence to the line so marked. (See “Can We Agree to Disagree?” POB Nov. 2010).

Early Pennsylvania case law includes several opinions that appear to be almost a perfect image of the previous Kentucky case:

That a consentable line may be established by parol which will, under certain circumstances bind the parties who assent thereto, is clearly established in Pennsylvania. In order, however, to make such a line binding it is necessary that there should be, first, a dispute; second, the establishment of a line settling the dispute; third, the consent of both parties to that line and the giving up of their respective claims which are inconsistent therewith.4

Perkins v. Gay is one of the first Pennsylvania decisions found that discusses consentable lines, and it would appear to be an index case on this principle as it is repeatedly cited in Pennsylvania common law to the present day. It discusses at length the difference between a boundary line agreement that is intended to be temporary, as opposed to one meant to be permanent. In the former scenario, landowners may agree to a line of convenience until the location of the true boundary line is determined, and neither the current owners subsequent to the determination of the line nor later purchasers would be bound by such an agreement. This opinion also holds that mutual mistake will often form a basis for agreements where owners will afterward be bound, provided that each party enters into the agreement with the understanding that some risk of loss is involved in any agreement of this type.

Another early Pennsylvania opinion equates the terms consentable and conditional lines:

An exception of “a small quantity struck off a tract by a conditional line,” it seems is void for uncertainty, if there is no such conditional line ascertained, or capable of being ascertained … In this country at that day consentable lines were not uncommon between settlers, and were often called conditional lines, lines to stand until they looked out the office rights.5

This case is of interest for two reasons: not only does it presume the words “consentable” and “conditional” are synonymous in this usage, but it also emphasizes that not all consentable lines will be considered valid, particularly when they fail to adequately define the location of the supposed agreement. In this example, it was stipulated that the call for the conditional line failed to indicate the identity of the parties creating the line or to indicate any monument, measurement or quantity by which the location of the line could be ascertained. By 1840, additional opinions had firmly established the concept of the consentable line by dispute and agreement in the Pennsylvania courts, but several additional refinements to this concept would develop during the next century.

When two landowners enter into some form of agreement to create a conditional or consentable boundary line, there is generally no guarantee one participant will enjoy equal gains or losses as opposed to the other. With the true location of the boundary unknown, it is in the nature of a gamble, where each adjoiner hopes the agreement will ultimately benefit him should the true location of the record boundary line be determined at some later time. Conversely, each party must also recognize the possibility that he may be left with the short stick.

The establishment of a consentable boundary line is always a matter of compromise, in which each party supposes he gives up for the sake of peace something to which in strict justice he is entitled. There is an express mutual abandonment of their former rights, upon an agreement, that whether they be good or whether they be bad … Each takes his chance of obtaining an equivalent for everything he relinquishes, and if the event turn out contrary to his expectations, so much the worse for him.6

Photos courtesy of Kristopher M. Kline

Recent Pennsylvania rulings emphasize the distinction between the doctrine of consentable lines as opposed to that of adverse possession, noting that consentable boundary lines do not require the actual use or physical possession of the entirety of the tract in question.7

The Kentucky courts have also attempted over the years to clarify the difference between prerequisites for a conditional/consentable line, as opposed to imperatives for a successful adverse possession claim.

While it is the rule that the owner of a tract, merely by extending its boundaries, does not take such adverse possession of the adjoining land embraced within the extension, overlapping the boundary of the adjoining owner, as would ripen into title, yet, where the dividing line is uncertain and in bona fide dispute as to its location, and a conditional line is established between the adjoining landowners, who agree as to its location and execute the agreement by marking the line, as by setting up stones and stakes at its corner or building a fence, such agreement is not an ineffectual settlement of their boundary controversy, nor is it prohibited by the statute of frauds. Because the parties do not thereby undertake to acquire and pass title to real estate, but simply by agreement fix and determine the situation and location of the thing that they already own, the purpose being to identify their several holdings by something agreed on, and to make certain that which they regarded as uncertain; such an agreement, followed by possession with reference to the boundary so fixed, is conclusive on the parties, it being sufficient to show that the dividing line was actually established and thereafter recognized or acquiesced in by the parties for a considerable time.8

Cassada also reports the two landowners (subsequent to the marking of the line with stones set in place) possessed openly and adversely in a hostile manner on opposite sides of the conditional line for a period of 25 years; the statutory requirement in Kentucky for an adverse possession claim is 15 years. Although adverse possession and conditional boundary line doctrine clearly differ, other examples exist where the Kentucky courts have described conditional lines existing as a result of adverse occupation over a great time span.9

As with many legal doctrines, failure to satisfy the requirements for conditional lines may result in the court rejecting the validity of the line in question. Two Arkansas cases emphasize this point. In one example, the conditional line is set aside because possession along the line in question only spanned a seven-year period, after which time the agreed upon line was apparently set aside by mutual consent of both parties.10 More recently, it was determined that a conditional line was considered by the adjoiners to be merely a best guess until such time as the true line was determined.11 Both Arkansas cases appear to reflect principles already exemplified by the Kentucky and Pennsylvania cases above.

The Kentucky courts likewise failed to uphold a supposed agreement to the top of a given mountain ridge as the agreed-upon boundary line in the case of Bringardner Lumber Co. v. Bingham; this would appear to have been a relatively easy decision to reach, since the court ruled that, of the four requirements found in Kentucky common law, the appellees failed to adequately prove any of the four.12

It will not come as a great surprise that fences often play a significant role in the determination of consentable boundary lines.13 The case of Dimura v. Williams differentiated adverse possession and consentable lines with regards to the type of fence found along the purported boundary lines:

While it is true that a fence must be substantial if the enclosure of land by such a fence is relied upon to sustain a claim of adverse possession, the law is different if a long-standing fence is relied upon for the establishment of a boundary between two adjacent parcels of land. The courts have always favored the settlement of boundary disputes by recognizing consentable lines established by the parties themselves, and this without regard to whether the line agreed upon conforms to the exact courses, distances, and bounds of the original surveys.14

Fences are also a significant factor in a more recent Pennsylvania case. In this example, the location of the boundary line was uncertain, and a surveyor was retained in 1952 to blaze and paint trees along the boundary line between plaintiff and defendant. Shortly thereafter, a single strand of fence wire was strung along the line surveyed; this was posted for the next 32 years. Additional evidence of possible acquiescence was demonstrated by the reposting of the line by both parties, the relocation of a logging road that crossed the marked line, and by selective harvesting of timber on one side of the line. When a later survey showed the record boundary line to be located some 700 feet west of that line marked by the 1952 survey, the defendants crossed over the previously marked line and posted the line as determined by the 1984 survey. The superior court concluded that use of the land was insufficient to establish title by adverse possession. However, the court made note that, while a single strand of fence wire was insufficient to prove a boundary by adverse possession, it would suffice under either theory for consentable boundary line.

This case, in addition to providing a fine example of the significance given to the type of fence line under different legal theories, also highlights a relatively recent addition to the doctrine of consentable lines in Pennsylvania. While early Pennsylvania common law principles that governed the creation of consentable lines tended to lean heavily on the well-established principles relating to parol agreements, it now appears that two distinct legal mechanisms for a legitimate consentable line have been codified by the Pennsylvania courts, characterized as (a) dispute and compromise, or (b) recognition and acquiescence.

The doctrine of consentable lines has emerged as a separate and distinct theory from that of traditional adverse possession. There are actually two ways in which one may prove a consentable line: by dispute and compromise, or by recognition and acquiescence … First, the court explained, one may prove a consentable line by evidence of:

(1) a dispute with regard to the location of a common boundary line, (2) the establishment of a line in compromise of the dispute, and (3) “the consent of both parties to that line and the giving up of their respective claims which are inconsistent therewith.” “[W]here such a line has been clearly established and the parties on each side take possession or surrender possession already held up to that line, it becomes binding, under the application of the doctrine of estoppel.”

Proof of a consentable line by recognition and acquiescence was explained by the same court as follows:

Our courts have long recognized, however, that a boundary line may be proved by a long-standing fence without proof of a dispute and its settlement by a compromise …

It cannot be disputed that occupation up to a fence on each side by a party or two parties for more than twenty-one years, each party claiming the land on his side as his own, gives to each an incontestable right up to the fence, and equally whether the fence is precisely on the right line or not.15 [emphasis added, cites omitted]

A fairly recent (1995) case also emphasizes that a consentable line does not constitute a conveyance of land within the meaning of the statute of frauds. As with other parol agreements, each owner holds up his own deed as the source of title, and the consentable line is considered to be a clarification of the descriptions contained in the deeds. In an unusual twist, the Pennsylvania court also concluded that tacking of the possessory interest on either side of a consentable line could be tacked (provided that privity of title exists between the various landowners).16

While emphasizing the problems inherent with any sort of parol boundary line agreement, these examples illustrate that consentable and conditional lines may at times be considered a legitimate--even beneficial--solution to the problem of a poorly defined boundary line, whether the original problem was caused by poor surveying practice, willful destruction of the original corner monumentation or merely the slow loss of boundary evidence over time. While the validity of existing conditional boundary lines will be determined by the courts, the surveyor will be instrumental not only in determining the location of the original boundary lines of record, but also in locating any evidence that may indicate the discrepancies between lines of record and lines of agreement.


1          Hoskins v. Boggs: 242 S.W.3d 320 Kentucky (2007)

2          Haag v. Wilson: 2010 Ky. App. Unpub.

3          Maynard v. Lowe: 231 Ky. 258; 21 S.W.2d 285 (1929)

4          Beals v. Allison: 161 Pa. Super. 125; 54 A.2d 84 (1947)

5          Stambaugh v. Hollabaugh: 10 Serg. & Rawle 357 Pa. (1823)

6          Beals v. Allison: 161 Pa. Super. 125; 54 A.2d 84 (1947)

7          Sorg v. Cunningham: 455 Pa. Super. 171; 687 A.2d 846 (1997)

8          Cassada v. Vanhook: 282 Ky. 383; 138 S.W.2d 1003 (1940)

9          Martin v. Oliver: 295 Ky. 624; 175 S.W.2d 127 (1943)

10        Wynn v. Garland: 19 Ark. 23 (1857)

11        Blackburn v. Coffee: 142 Ark. 426; 218 S.W. 836; 1920)

12        Bringardner Lumber Co. v. Bingham: 251 S.W.2d 273 Ky. (1952)

13        DiVirgilio v. Ettore: 188 Pa. Super. 526; 149 A.2d 153 (1959)

14        Dimura v. Williams: 446 Pa. 316; 286 A.2d 370 (1972)

15        Niles v. Fall Creek Hunting Club: 376 Pa. Super. 260; 545 A.2d 926 (1988)

16        Plauchak v. Boling: 439 Pa. Super. 156; 653 A.2d 671 (1995)