Boundary Dispute Case Law Alder v White
In Boundary Dispute Case Law Alder v White (2025), the Court of Appeal addressed a critical legal question: does a boundary agreement between neighbours bind successors in title, and if so, must those successors have knowledge of the agreement for it to be effective?
This judgment offers authoritative clarification on the enforceability of boundary demarcation agreements and firmly places the reasoning in Neilson v Poole as the prevailing legal position, reaffirming that such agreements have proprietary effect and are binding irrespective of a successor’s knowledge.
Background
The dispute arose between Darren White (Appellant) and Professor and Mrs Alder (Respondents), who owned adjacent properties in Fuller Street, Fairstead, Chelmsford—Willow Cottage and The Old Stores respectively.
Both parties had purchased their properties in November 2005, with the Alders acquiring theirs just nine days before Mr White.
Before these transactions, the previous owners of both properties—Hobsons (for Willow Cottage) and Joneses (for The Old Stores)—had agreed on the boundary line.
The parties formed this agreement in October 2005 and later documented it in writing with a textual description and an accompanying plan.
Years later, Mr White began building works that allegedly encroached onto the Alder’s land. The Alders initiated proceedings in 2020, seeking declarations and injunctive relief based on the pre-existing boundary agreement.
Central to the case was whether this agreement, made between prior owners, legally bound Mr White as a successor in title.
Procedural History
The Court limited the initial trial to preliminary issues, specifically addressing the existence and legal effect of the boundary agreement.
District Judge Mills held that:
- A valid boundary agreement had been made between the predecessors in title.
- It was an agreement to clarify an uncertain boundary—not a contract to convey land.
- The agreement was binding on successors in title, including Mr White.
Mr White appealed on five grounds. The Court dismissed four of the claims early, and HHJ Duddridge heard the fifth—concerning the binding nature of the agreement—and dismissed it as well.
The judge affirmed the earlier decision, aligning with long-standing case law that boundary agreements of a demarcation nature bind successors regardless of their knowledge.
The Court granted permission for a further appeal to the Court of Appeal on this fifth ground, specifically to address whether such agreements bind successors in title who lack actual or constructive knowledge of them.
Issues on Appeal
The two grounds of appeal before the Court of Appeal were:
- Whether the judge was wrong to reject the interpretation of <em>Gibson v New</em> that boundary agreements are not binding on successors in title.
- Whether, even if they are binding, the agreement should not bind Mr White due to his lack of knowledge at the time of purchase.
The Alders, via a Respondent’s Notice, argued that binding precedent—Burns v Morton and Stephenson v Johnson—necessitated the same outcome even if the appeal succeeded on its own terms.
Legal Analysis and Precedent Review
Binding Precedent: Neilson v Poole
The Court of Appeal examined the seminal authority Neilson v Poole (1969), in which Megarry J held that boundary demarcation agreements merely clarify uncertain boundaries and do not amount to contracts for the conveyance of land. Such agreements, therefore, do not require registration and are binding on successors.
Megarry J distinguished between two types of boundary agreements:
- Those that transfer land, requiring formal conveyance.
- Those that demarcate uncertain boundaries, which are presumed not to convey land and are binding on successors by their nature.
Subsequent cases have repeatedly endorsed this reasoning, including:
1. Joyce v Rigolli (2004)
2. Haycocks v Neville (2007)
3. Stephenson v Johnson (2000)
4. Burns v Morton (2000)
These decisions reinforce the principle that demarcation agreements define the extent of title conveyed in subsequent transfers, giving them proprietary effect.
Relevance of Gibson v New
Mr White relied heavily on Gibson v New (2021), arguing it stood for the proposition that boundary agreements do not bind successors. The Court rejected this argument, finding that the relevant observations in Gibson were not legally binding and did not directly engage with the authority in Neilson.
In Gibson, the Court considered whether a mediation-based settlement agreement between the original parties was binding, without any claim that the successors in title were involved. As such, it could not displace the clear line of binding authority established in Neilson and affirmed in multiple Court of Appeal decisions.
Court of Appeal's Conclusion - Boundary Dispute Case Law Alder v White
Lady Justice Asplin, delivering the lead judgment, comprehensively reviewed the jurisprudence. She reaffirmed that:
- Boundary demarcation agreements bind successors in title.
- This binding effect arises because the agreement defines the physical extent of the property conveyed—successors acquire what their predecessor owned, not more.
- The agreement operates as a delineation of legal title, not as a personal contractual obligation.
- Knowledge of the agreement by the successor is not required.
The Court held that public policy supports the certainty provided by demarcation agreements. Requiring formal conveyance or successor knowledge would reintroduce litigation and uncertainty, undermining their very purpose.
As Asplin LJ stated, the agreement "establishes on the ground the physical extent of the respective legal estates" and is "presumed to be the true and ancient limits." Accordingly, successors take subject to the boundary thus defined, regardless of their awareness.
Key Takeaways from Boundary Dispute Case Law Alder v White
1. Boundary demarcation agreements bind successors in title even if the successor has no knowledge of the agreement. The agreement defines what the successor acquires.
2. Demarcation agreements are not contracts to convey land, and therefore do not require compliance with formalities under the Law of Property (Miscellaneous Provisions) Act 1989 or registration under the Land Charges Act 1925.
3. Public policy strongly favours such agreements as they promote peace and clarity between neighbours, reduce litigation, and preserve the integrity of property boundaries.
4. The Court distinguished Gibson v New as non-binding on this point, finding its remarks were obiter and did not overturn the principles in Neilson v Poole.
5. The extent of a party’s registered title is subject to prior demarcation agreements—a purchaser can only acquire what their vendor owned, no more.
6. There is no requirement for successors to prove adverse possession or estoppel in addition to a valid demarcation agreement. The agreement alone can define title boundaries conclusively.
7. Boundary demarcation agreements apply equally to registered and unregistered land, as general boundaries shown on title plans may be clarified by prior agreement.
8. The Court confirmed that the appeal process will not entertain new legal arguments at a late stage unless certain conditions are met—however, the Court allowed the broader legal issue (knowledge requirement) to be addressed as intrinsic to the appeal.
9. Surveyors and conveyancers should carefully record and preserve any boundary agreements, as their legal effect can persist and bind successors indefinitely.
10. Alder v White reinforces the evidential and legal strength of boundary agreements, making them a critical tool in resolving neighbour disputes and determining property extents.
Need Advice on a Boundary Dispute?
At Anstey Horne, our expert team of chartered surveyors specialises in resolving complex boundary disputes across England and Wales. Whether you’re a property owner, developer, or legal advisor, we provide:
- Independent boundary determinations
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- Negotiation and mediation support
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For more information on all aspects of Boundary Disputes see the collection of articles in our blog.
For advice direct from one of our Surveyors, please call our Enquiry line on 020 4534 3135.
If you are planning work that is covered by the Act, or if you have received notice of work from a neighbour and want advice on how best to protect your property please contact:
Geoffrey Adams
BEng (Hons) PgDip FRICS
Senior Director
Party Walls
London
Rickie Bloom
BSc (Hons) MRICS
Senior Director
Party Walls
London