No Duty to Disclose Zoning; County Website Errors and Bidder Mistake Are Not “Irregularities” Permitting Rescission of Delaware Sheriff’s Sales

Introduction

In 248 Glenn Cove CP, LLC v. Delva Solutions, LLC (Del. Oct. 9, 2025), the Delaware Supreme Court affirmed the Superior Court’s refusal to set aside a Sheriff’s sale after the successful bidder, 248 Glenn Cove CP, LLC (“Glen Cove”), discovered that its planned use of the property was not permissible under the Town of Middletown’s land use restrictions. The bidder argued that it had relied on New Castle County’s tax parcel website, which identified the parcel as commercially zoned with five rental units, and that neither the Sheriff nor the foreclosing mortgagee (Delva Solutions, LLC) disclosed any contrary zoning constraints at the sale. The Supreme Court held that none of this amounted to an “irregularity” under Superior Court Civil Rule 60(b); that any equitable estoppel claim was waived and, in any event, unsatisfied on the merits; and that a newly raised “mutual mistake” theory was both waived and substantively defective.

The decision underscores core principles governing Delaware Sheriff’s sales: finality; the bidder’s responsibility to perform independent due diligence; the limited and process-focused concept of “irregularity”; and the strict application of waiver rules on appeal. Most notably, the Court made clear that a buyer’s reliance on general public information—such as a county parcel website—does not reallocate the due diligence burden or create a duty on the Sheriff or foreclosing creditor to disclose zoning developments. A misunderstanding about zoning or permitted uses is not, without more, a basis to unwind a judicial sale.

Summary of the Opinion

Glen Cove purchased 102 South Broad Street in Middletown, Delaware, at a December 10, 2024 Sheriff’s sale initiated by mortgagee Delva Solutions. Before the sale, Glen Cove reviewed the New Castle County tax parcel website, which indicated a commercial building with five rentable units. After the sale, an architect advised that the Town of Middletown would only permit single-family residential uses. Glen Cove then stopped payment on its $61,000 check. Delva moved in Superior Court to confirm the sale; Glen Cove sought to set it aside, arguing equitable estoppel and the presence of “irregularities” in the sale because the County’s website was inaccurate and the Sheriff failed to warn about zoning.

The Superior Court denied the motion, finding that any reliance on the Sheriff was unreasonable and that Glen Cove’s failure to conduct its own due diligence was the root cause of its predicament. On appeal, the Supreme Court:

Affirmed, holding that alleged mistakes about zoning and reliance on the County’s website did not constitute an “irregularity” in the sale process under Rule 60(b);
Held that Glen Cove’s equitable estoppel argument was waived for inadequate briefing, and would fail on the merits because Glen Cove could have obtained the information by contacting Middletown and had not relied on the conduct of the parties it sought to estop;
Held that Glen Cove’s mutual mistake theory was waived because it was not raised below; and, even if considered, would fail for lack of a specific shared understanding between Delva and the unknown ultimate buyer.

The Court emphasized the Superior Court’s broad discretion to confirm Sheriff’s sales and the high threshold for setting them aside, which applies only to rectify a plain injustice grounded in an irregularity in the judicial process—not a bidder’s post-sale regret or curable due diligence failures.

Analysis

Precedents Cited and Their Influence

Fitzsimmons v. New Castle County, 827 A.2d 30, 2003 WL 21556987 (Del. July 7, 2003) (TABLE): Cited for the standard of review—legal determinations are reviewed de novo. This framed the Court’s review of what qualifies as an “irregularity” and whether equitable doctrines applied.
Shipley v. New Castle County, 975 A.2d 764 (Del. 2009): Provided both the deferential abuse of discretion review of the Superior Court’s decision to confirm a Sheriff’s sale and the “shocks the conscience” yardstick for price-based challenges. The Court relied on Shipley to reiterate that sales are not undone lightly and only when extraordinary circumstances are shown; mere errors in description or price deviations typically do not suffice.
Deibler v. Atlantic Properties Group, Inc., 652 A.2d 553 (Del. 1995), quoting Firestone Tire & Rubber Co. v. Adams, 541 A.2d 567 (Del. 1988): Emphasized the Superior Court’s broad discretion and the limited circumstances under which an appellate court will find an abuse. The Court invoked this line to confirm that discretion was properly exercised here.
Deutsche Bank Nat. Tr. Co. v. Goldfeder, 86 A.3d 1118, 2014 WL 644442 (Del. 2014) (TABLE): Clarified when a court “exceeds” its discretion—by arbitrarily refusing to confirm a sale without irregularities or fraud. The Court used this to demonstrate that the Superior Court acted well within bounds.
Burge v. Fidelity Bond & Mortgage Co., 648 A.2d 414 (Del. 1994): Set the core policy: Sheriff’s sales should not be set aside for trivial reasons, and relief is reserved for correcting a plain injustice consistent with equity. The Court cited Burge both for this principle and to contrast the exceptional case in which unilateral mistakes by a foreclosing mortgagee warranted relief.
In re Downham Co., 165 A. 152 (Del. Super. 1932): Longstanding authority for the “shock the conscience” threshold on price inadequacy, often operationalized as roughly 50% or less of true value. The Court cited this to underscore how high the bar stands for price-based “irregularity” claims.
LSF9 Master Participation Tr. v. Truitt, 2017 WL 8787509 (Del. Super. Oct. 24, 2017): A recent application rejecting a non-shocking price defect as an “irregularity.” Reinforced that not every sale mistake qualifies for relief.
Smith v. Caldera Props.-Nassau Grove, LLC, 2011 WL 2420842 (Del. Super. June 9, 2011): Upheld confirmation despite an extremely low sale price because parties could have protected themselves. Supports the Court’s allocation of responsibility to bidders for their own diligence.
Williams Companies, Inc. v. Energy Transfer Equity, L.P., 159 A.3d 264 (Del. 2017): Provided the elements of equitable estoppel, including the inability to obtain the information and reliance on the conduct of the party to be estopped. The Court used Williams to show estoppel’s inapplicability: Glen Cove could have called the Town, and its claimed reliance was on the County, not Delva or the Sheriff.
Cerberus Int’l, Ltd. v. Apollo Mgmt., L.P., 794 A.2d 1141 (Del. 2002): Articulated the contract doctrine of mutual mistake, which requires a specific, shared prior understanding. The Court distinguished this doctrine as inapplicable to a Sheriff’s sale absent evidence that the mortgagee and the unknown successful bidder shared a specific prior understanding about permitted uses.

Legal Reasoning

The Court’s reasoning proceeded on three tracks—waiver, the scope of “irregularity” under Rule 60(b), and the bidder’s due diligence obligations.

Waiver principles controlled two of Glen Cove’s theories:
- Equitable estoppel was deemed waived because the brief’s heading mentioned it but the argument body did not develop it. Even if considered, the elements were not satisfied: Glen Cove could have obtained the relevant zoning-use information by contacting the Town of Middletown, and its claimed reliance was on the County’s website, not on statements or conduct by Delva or the Sheriff—the parties Glen Cove sought to estop.
- Mutual mistake was raised for the first time on appeal and was therefore waived under Supreme Court Rule 8. The Court added that, on the merits, the doctrine would be unavailable because there was no clear and convincing evidence that Delva and Glen Cove shared a specific prior understanding about permitted uses. In the setting of a Sheriff’s sale—where the buyer is unidentified in advance—it is “illogical” to posit such a bilateral understanding between mortgagee and eventual buyer.
“Irregularity” under Rule 60(b) is a process-focused concept. The Court reaffirmed that not every mistake counts as an irregularity warranting relief. Relief is reserved for circumstances that would “correct a plain injustice,” and price-related claims require a result that “shocks the sense of the court.” Mistakes in external information sources or a bidder’s misunderstanding of property characteristics are not ordinarily defects in the judicial process.
Due diligence is the bidder’s responsibility. The Superior Court found that Glen Cove’s problem flowed from its own failure to contact the Town, particularly given that its architect knew to do so. The Sheriff and Delva had no duty to vet zoning or to caution bidders that zoning can change or that municipal constraints may override assumptions. The Supreme Court endorsed these findings, concluding that any error here was a bidder-side diligence lapse, not a procedural irregularity.
The Court also rejected Glen Cove’s attempt to recast its reliance exclusively on the County’s website. Glen Cove had, in fact, argued below that the Sheriff’s non-disclosure was an irregularity. The Superior Court’s observation that any reliance “to the extent” it existed on the Sheriff was unreasonable was therefore not clearly erroneous. More broadly, neither the Sheriff’s silence nor the County’s website transformed bidder-side assumptions into an irregularity.

Impact and Significance

This decision reinforces several important propositions that will influence foreclosure practice and bidder behavior in Delaware:

Bidders bear the risk of regulatory and zoning uncertainties. Sheriff’s sales are “as is, where is” in effect; bidders must independently verify land use permissions with the governing jurisdiction. Reliance on a county parcel website—or similar public information—does not substitute for direct confirmation with the municipal authority having zoning power.
Government websites do not create sale “irregularities.” Misstatements or outdated information on public databases do not render the judicial sales process defective. They are external to the process and, without more, cannot justify rescission.
No affirmative disclosure duty rests on the Sheriff or foreclosing creditor to warn about zoning or possible changes. The Court’s affirmation signals that silence on such matters is not unfairness or an irregularity.
Appellate waiver rules are strictly applied. Parties must fully brief equitable and contractual theories in the trial court, and must develop arguments on appeal beyond headings. Failure to do so forfeits review.
The high threshold for undoing Sheriff’s sales remains intact. Courts will continue to prioritize finality and market confidence in foreclosure auctions. Only process defects, fraud, or plainly unjust circumstances—such as those meeting the “shock the conscience” standard—will warrant setting aside a sale.
Practical implications: Investors and counsel should adjust pre-bid checklists to include direct communications with the relevant municipality regarding permitted uses, zoning overlays, nonconformities, and pending ordinances. Architects’ or planners’ preliminary scoping should occur before bidding, not after.

Complex Concepts Simplified

Irregularity in the sale process: A defect in how the judicial sale was conducted (e.g., procedural noncompliance, fraud, or unfairness) that undermines the fairness of the proceeding. Not every mistake (like an external database error or a bidder’s misunderstanding) qualifies. Relief aims to correct a “plain injustice,” not to insure bidders against their own diligence gaps.
“Shocks the conscience” price standard: An exceptionally low sale price—often conceptualized as around 50% or less of true value—may be so inadequate that it signals an irregularity, especially when paired with other indicia of unfairness.
Equitable estoppel: Prevents a party from asserting a position when, among other elements, (a) the other side could not obtain the relevant information and (b) reasonably relied on the conduct of the party to be estopped. Here, the buyer could have called the Town, and any reliance was on the County’s website—not on conduct by the Sheriff or Delva.
Mutual mistake (contract doctrine): Allows rescission when both parties shared a specific mistaken belief about a basic assumption at the time of contracting. In a Sheriff’s sale, the mortgagee typically has no specific shared understanding with an unknown future bidder about the bidder’s intended uses, so the doctrine is a poor fit absent unusual facts.
Waiver on appeal: Arguments not raised below (or raised but not substantively briefed on appeal) are forfeited and will not be considered, absent limited exceptions not applicable here.

Conclusion

The Delaware Supreme Court’s decision in 248 Glenn Cove CP, LLC v. Delva Solutions, LLC fortifies the longstanding finality of Sheriff’s sales and clarifies that bidder-side misunderstandings about zoning or reliance on government websites do not amount to “irregularities” under Rule 60(b). The Sheriff and the foreclosing mortgagee have no duty to disclose zoning or warn that municipal land-use restrictions may constrain future uses. Equitable estoppel and mutual mistake provide no escape hatch where the bidder could have obtained the information and lacks a specific shared understanding with the seller.

The key takeaway is practical and doctrinal: in Delaware foreclosure auctions, bidders must perform their own, pre-bid, municipality-focused due diligence on zoning and permitted uses. Courts will not convert post-sale disappointment into process defects, and they will apply waiver rules strictly. The decision thus promotes certainty and encourages robust participation at judicial sales, while allocating diligence burdens squarely on those who choose to bid.