Title: Delaware v. Monsanto Company

State: delaware

Issuer: Delaware Supreme Court

Document:

IN THE SUPREME COURT OF THE STATE OF DELAWARE 
 
STATE OF DELAWARE, ex rel.  
 § 
KATHLEEN JENNINGS, Attorney  § 
General of the State of Delaware, 
 §  
No. 279, 2022 
 
 
 
 
 
 
 §  
 
 
Plaintiff Below, 
 
 
 §  
Court Below: Superior Court 
 
Appellant,  
 
  
 §  
of the State of Delaware 
 §  
 
v. 
 
 
 
 
 § 
C.A. No. N21C-09-179 
 § 
 
MONSANTO COMPANY, 
  
 § 
SOLUTIA, INC., and 
 
 
 § 
PHARMACIA LLC, 
 
 
 §  
 
 
 
 
 
 
 
 §  
 
 
 
Defendants Below, 
 
 
 § 
 
Appellees.  
 
 
 § 
 
 
 
 
 
 
Submitted:  March 29, 2023 
Decided:  
June 22, 2023 
 
Before SEITZ, Chief Justice; VALIHURA, VAUGHN and TRAYNOR, Justices; 
MCCORMICK, Chancellor,1 constituting the Court en Banc. 
 
Upon appeal from the Superior Court.  AFFIRMED IN PART AND REVERSED 
IN PART. 
 
Ralph K. Durstein III, Esquire (argued), Christian Douglas Wright, Esquire, 
DELAWARE DEPARTMENT OF JUSTICE, Wilmington, Delaware; Alison S. 
Gaffney, Esquire, Daniel Mensher, Esquire, KELLER ROHRBACK L.L.P., Seattle, 
Washington; Keil Mueller, Esquire, Steven C. Berman, Esquire, STOLL STOLL 
BERNE LOKTING & SHLACHTER P.C., Portland, Oregon, for Plaintiff Below, 
Appellant State of Delaware. 
 
Christian J. Singewald, Esquire, Timothy S. Martin, Esquire, Daryll Hawthorne-
Searight, Esquire, WHITE AND WILLIAMS LLP, Wilmington, Delaware; Kim 
 
1 Sitting by designation under Del. Const. art. IV, § 12 and Supreme Court Rules 2(a) and 4(a) to  
complete the quorum. 
2 
 
Kocher, Esquire (argued), Thomas M. Goutman, Esquire, David S. Haase, Esquire, 
SHOOK, HARDY & BACON L.L.P., Philadelphia, Pennsylvania, for Defendants 
Below, Appellees Monsanto Company, Solutia, Inc., and Pharmacia LLC.  
 
Kenneth T. Kristl, Esquire, WIDENER UNIVERSITY DELAWARE LAW 
SCHOOL, Wilmington, Delaware as Amici Curiae Legal Scholars, in support of 
Appellant. 
 
Richard L. Renck, Esquire, Mackenzie Wrobel, Esquire, Michael Gonen, Esquire, 
DUANE MORRIS LLP, Wilmington, Delaware; Robert M. Palumbos, Esquire, 
DUANE MORRIS LLP, Philadelphia, Pennsylvania; Jonathan Urick, Esquire, U.S. 
CHAMBERS OF COMMERCE, Washington, D.C., as Amici Curiae the Chamber 
of Commerce of the United States of America, the American Tort Reform 
Association, and the American Coatings Association in support of Appellees. 
 
Anne M. Steadman, Esquire, REED SMITH LLP, Wilmington, Delaware; James C. 
Martin, Esquire, REED SMITH LLP, Pittsburgh, Pennsylvania, as Amicus Curiae 
The Product Liability Advisory Council in support of Appellee. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3 
 
SEITZ, Chief Justice: 
According to the allegations of the complaint, for over forty years, Monsanto 
was the only U.S. manufacturer of polychlorinated biphenyls, or “PCBs.”  PCBs are 
forever chemicals that, when released into the environment, persist indefinitely.  
PCB exposure has been linked to many serious health effects, so much so that the 
federal government in 1977 banned PCB production.  The federal government and 
the states have spent enormous sums cleaning up PCB environmental contamination.  
The State of Delaware is no exception. 
The State alleged that Monsanto knew that the PCBs it produced and sold to 
industry and to consumers would eventually be released into the environment and 
would cause lasting damage to public health and the State’s lands and waters.  The 
State brought this action to hold Monsanto responsible for its cleanup costs.  It 
asserted claims for public nuisance, trespass, and unjust enrichment.   
The Superior Court dismissed the complaint.  The trial court reasoned that, 
even though the State alleged that Monsanto knew for decades that PCBs were toxic 
and would contaminate the environment for generations, the State could not assert a 
public nuisance claim or trespass claim because Monsanto manufactured PCB 
products, which entered the environment after sale to third parties.  The court also 
found that the State did not have standing to bring a trespass claim because it held 
public lands in trust rather than outright and therefore did not have the exclusive 
4 
 
possession of land needed to assert a trespass claim.  And the court held that the 
Superior Court lacked subject matter jurisdiction to hear the unjust enrichment claim 
as a standalone claim.  It also concluded that the State could not use an unjust 
enrichment claim to recover future cleanup costs. 
On appeal, the State argues that there is no product-based exclusion or control 
element of a public nuisance or trespass claim.  According to the State, it is enough 
to allege that Monsanto substantially contributed to causing the public nuisance and 
trespass by selling PCBs to others knowing their end use would cause widespread 
and lasting environmental contamination.  In addition, for its trespass claim, the 
State contends that it has exclusive possession of lands it owns directly and of lands 
it holds in trust and thus has standing to assert the claim.  Finally, the State argues 
that it need not demonstrate the lack of a remedy at law for the Superior Court to 
have jurisdiction to hear its unjust enrichment claim, and it sufficiently alleged how 
Monsanto has been unjustly enriched. 
The Superior Court held correctly that the State lacks standing to pursue a 
trespass claim for land it holds in trust because it does not have exclusive possession 
of those lands.  And while the Superior Court does have jurisdiction to consider an 
unjust enrichment claim, we agree with the court that the State cannot assert the 
claim to recover PCB cleanup expenses because Monsanto did not owe a legal duty 
independent of its public nuisance and trespass claims.   
5 
 
However, we disagree with several of the Superior Court’s rulings.  First, 
whether a product is involved, and whether there is control of the product once sold, 
are not elements of an environmental-based public nuisance or trespass claim under 
Delaware law.  For environmental public nuisance and trespass claims, the question 
is whether the defendant participated to a substantial extent in carrying out the 
activity that created the public nuisance or caused the trespass.  Here, the State has 
pled sufficiently that, even though Monsanto did not control the PCBs after sale, it 
substantially participated in creating the public nuisance and causing the trespass by 
actively misleading the public and continuing to supply PCBs to industry and 
consumers knowing that PCBs were hazardous, would escape into the environment 
after sale to third parties, and would lead to widespread and lasting contamination 
of Delaware’s lands and waters.  Second, the State alleged that it owns some land 
directly – not in trust – and therefore has the exclusive possession of that land needed 
to assert a trespass claim.  Thus, we affirm in part and reverse in part, and remand 
for further proceedings consistent with this opinion.       
I. 
A. 
At this stage of the litigation, we accept the well-pled allegations of the 
complaint as true.2  In 1929, Swann Research, Inc. began commercial production of 
 
2 Central Mortg. Co. v. Morgan Stanley Mortg. Capital Hldgs. LLC, 27 A.3d 531, 535 (Del. 2011). 
6 
 
PCBs in the United States.3  Six years later, Monsanto purchased Swann Research.  
From 1930 to 1977, Monsanto was the only manufacturer of PCBs for widespread 
commercial use in the United States.4 
PCBs are a group of synthetic chemical compounds with unique qualities that 
make them useful in commercial products.5  They are fire resistant, minimally water 
soluble, chemically stable, and have excellent dielectric properties.6  They can 
persist in the natural environment for centuries.  But human exposure to PCBs “can 
cause serious liver damage, depressed immune system function, skin conditions such 
as acne and rashes, significant irritation of and harm to the nose and lungs, 
gastrointestinal discomfort, changes in the blood and liver, depression, fatigue, and 
learning capacity impairment.”7  In children, PCBs can alter their development, and 
exposure can happen prenatally or through breast milk.8  The Environmental 
Protection Agency (the “EPA”) declared PCBs as probable carcinogens.  PCBs also 
have harmful non-carcinogenic effects on the immune, reproductive, nervous, and 
endocrine systems of humans.9   
 
3 App. to Opening Br. at A022 (the complaint). 
4 Id. 
5 Id. at A018-19. 
6 Id. A020. 
7 Id. 
8 Id. at A021. 
9 Id. 
7 
 
PCBs are harmful to animals, including fish, mammals, pinnipeds, and birds.  
In animals, PCBs “accumulate in lipid rich tissues and substances, such as the fatty 
tissues of wildlife, birds, fish, and other animal life.”10  One study found a correlation 
between PCB exposure and a decline in population and reproduction impairment in 
minks and certain bird species.11  Once PCBs enter the environment, they “are 
transported through soil, sediment, air, and water,” and humans and animals are 
exposed to PCBs through ingestion, inhalation, or direct contact.12 
B. 
According to the complaint, Monsanto knew since 1937 about the negative 
effects of PCBs.  That year, it circulated an internal memorandum that explained the 
toxic effects PCBs had on humans and animals.13  Yet, it continued to “develop[], 
produce[], and market[] PCBs for use in a wide range of commercial and industrial 
applications,” without warning to the public.14  Monsanto manufactured a total of 
641,246 metric tons of PCBs in the United States between 1930 and 1977.15   
PCBs “were advertised and predominantly used as components of dielectric 
fluids—materials used for electrical insulation—in capacitors, transformers, and 
 
10 Id. at A020. 
11 Id. at A022. 
12 Id. at A026. 
13 Id. at A027. 
14 Id. at A023.  
15 Id.  
8 
 
other electrical systems.”16  PCBs entered the environment through the use in both 
open and closed products.  In “open applications” – coolants, flame retardants, 
plasticizers, paint, etc. – PCBs entered the environment through usage.17  Closed 
applications emitted PCBs through “leaks, maintenance, or by volatilizing into the 
air.”18   
Monsanto knew as early as the 1950s that PCBs escaped into the 
environment.19  In the 1950’s and 60’s, scientists reported on the widespread and 
harmful effects of PCBs.  But Monsanto “repeatedly misrepresented those facts, 
telling consumers, the public, and government entities the exact opposite—that the 
compounds were not toxic and that the company would not expect to find PCBs in 
the environment in a widespread manner.”20 
In 1947, in response to a customer’s inquiry about the hazards of PCBs, 
Monsanto told the customer that Aroclor 1268, one of its PCB products, was almost 
non-toxic, “but ‘[t]he vapors of other Aroclors studied are toxic and should be 
avoided.’”21  In 1949, it created its own statement regarding the risks of PCBs to 
distribute to inquiring clients and customers: 
TOXICITY—Prolonged exposure to AROCLOR vapours will lead to 
systemic toxic effects.  However, this is not significant except at high 
 
16 Id. 
17 Id. at A023-24. 
18 Id. at A024. 
19 Id. at A031. 
20 Id. at A043. 
21 Id. at A028 (alteration in original). 
9 
 
temperatures and then normal draught ventilation will remove any risk.  
[] Acne-form skin eruptions may arise from continued bodily contact 
with liquid AROCLORS, but normal precautions and, if necessary, 
suitable garments provide adequate protection.  Toxic effects will 
follow considerable oral ingestion, but this hazard is unlikely to be 
encountered.22 
In March 1969, Monsanto wrote the Los Angeles County Air Pollution 
Control District and advised that “the Aroclor compounds ‘are not particularly toxic 
by oral ingestion or skin absorption.’”23  Later in that same year, it told the New 
Jersey Department of Conservation that “[b]ased on available data, manufacturing 
and use experience, we do not believe the PCBs to be seriously toxic.”24  It also tried 
to persuade the U.S. Navy to use PCBs in its submarines after the Navy conducted 
its own independent research and concluded that PCBs were too dangerous to use.25 
In the 1960s, Monsanto promoted and marketed the use of PCBs in a wide 
variety of common household items, although Monsanto tried to distance itself from 
the use of PCBs in household items by 1970.26  In a press release Monsanto stated 
that “PCB was developed over 40 years ago primarily for use as a coolant in 
electrical transformers and capacitors.  It is also used in commercial heating and 
cooling systems.  It is not a ‘household’ item.”27  At the time, however, Monsanto 
 
22 Id. 
23 Id. at A043. 
24 Id. at A044 (alteration in original). 
25 Id. at A030. 
26 Id. at A042-43. 
27 Id. at A043. 
10 
 
was still marketing and selling PCB compounds for use in common household 
items.28 
Monsanto’s representations about the relative safety of PCBs were 
inconsistent with the evidence in its possession.  In 1953, Monsanto’s manager of 
environmental health sent an internal memorandum to its chief chemist, noting that 
PCBs could not be considered nontoxic.  In another internal report two years later, 
its chief chemist attached to the report an article that stated that the toxicity of PCBs 
had been repeatedly demonstrated.29  Monsanto also ignored its own research in 
1966 that “demonstrated the seemingly limitless potential of PCBs for 
environmental destruction.”30 
In 1969, when the toxicity evidence became overwhelming, Monsanto 
“formed an ‘Aroclor Ad Hoc Committee,’ and tasked that committee with preparing 
recommendations for actions that Monsanto could take to improve its reputation and 
salvage its bottom line.”31  The committee reported two key findings: 
The committee believes there is little probability that any action that 
can be taken will prevent the growing incrimination of specific 
polychlorinated biphenyls (the higher chlorinated—e.g. Aroclors 1254 
and 1260) as nearly global environmental contaminants leading to 
contamination of human food (particularly fish), the killing of some 
marine species (shrimp), and the possible extinction of several species 
of fish eating birds.  
 
28 Id. 
29 Id. at A029. 
30 Id. at A034. 
31 Id. at A037. 
11 
 
Secondly, the committee believes that there is no practical course of 
action that can so effectively police the uses of these products as to 
prevent environmental contamination.  There are, however, a number 
of actions which must be undertaken to prolong the manufacture, sale 
and use of these particular Aroclors as well as to protect the continued 
use of other members of the Aroclor series.32 
In response to the committee’s findings, in 1970, Monsanto circulated an 
interoffice memorandum and updated its previous customer statements from 1947.  
In the memorandum, Monsanto acknowledged the harmful effects of PCBs but 
reiterated that Monsanto would continue to make PCBs because “[w]e can’t afford 
to lose one dollar of business.”33  The memorandum “provided talking points for 
[Monsanto’s] employees when discussing the dangers of PCBs with inquiring 
customers.”34  Monsanto instructed employees “to avoid any situation where a 
customer wants to return fluid.”35  In the year following the Ad Hoc Committee 
formation and circulation of the memorandum, Monsanto’s PCB production reached 
a company-high of 85 million pounds.36 
Monsanto continued to sell PCBs until 1977, when the federal government 
prohibited their manufacture and sale.37   
 
 
32 Id. at A038 (emphasis omitted). 
33 Id. at A040 (alteration in original).  
34 Id. 
35 Id. 
36 Id. at A040-41.  
37 Id. at A014. 
12 
 
C. 
Even though PCB production ceased in 1977, PCBs continue to contaminate 
the natural environment.  Delaware in particular has “investigated, monitored, and 
detected the presence of PCBs on its lands, in its waters, and in various wildlife 
species and other public trust resources within its borders.”38  PCBs have been 
detected in the Delaware River, Delaware Bay, Christina River, a variety of 
privately-owned contaminated sites located within the State, the Amtrak rail yards, 
CitiSteel, Governor Bacon Health Center/Fort DuPont State Park,39 and other State-
owned lands and public trust resources.  The State has “develop[ed] innovative 
clean-up strategies, including deploying PCB-destroying microorganisms and 
adding activated carbon and quicklime to sediments that bind contaminants and limit 
their transfer to the water and fish.”40 
D. 
Against this backdrop, on September 22, 2021, the State of Delaware became 
the latest of many states to file suit against Monsanto to recover damages for harm 
 
38 Id. A046 (the complaint). 
39 As alleged, the State-owned land is “located on the grounds of a former military base dating 
back to the Civil War, which was sold to the State in 1947.  Near the health center and the state 
park is a former landfill in which PCB-containing materials were deposited.  Both state and federal 
agencies have undertaken cleanup, with the EPA removing PCB-contaminated soil from the area 
and DNREC performing treatment to eliminate hazardous runoff from the site.” Id. at A055. 
40 Id. at A058. 
13 
 
suffered due to the manufacturing of PCBs.41  The State asserted three claims – 
public nuisance, trespass, and unjust enrichment.   
For its public nuisance claim, the State alleged that the “continuous presence 
of PCBs on lands and in waters that the State owns or holds in trust . . . presents 
ongoing risks to the health of humans, fish, wildlife, and the environment in the State 
of Delaware and constitutes an unreasonable interference with rights common to the 
general public.”42  For the trespass claim, it alleged that the presence of PCBs “on 
or in waters, land, and other public trust resources of the State interferes with the 
State’s interest in the exclusive possession of that property and thereby constitutes a 
trespass.”43  It also alleged that Monsanto “had no license or other authorization to 
enter onto or leave contaminants on property that the State possesses.”44  For the 
unjust enrichment claim, the State alleged that it had incurred significant 
investigation, monitoring, and remedial costs in abating the hazard and the risk PCBs 
pose to public health and safety.   
For all claims, the State alleged that Monsanto knew as early as 1937 of the 
hazardous effects of PCBs in the environment but ignored the evidence and took 
 
41 Around 1977, Monsanto restructured into three separate entities: Monsanto Company, Solutia, 
Inc., and Pharmacia LLC.  Monsanto now “operates Original Monsanto’s agricultural products 
business.”  Id. at A015.  Solutia “has assumed all operations, assets, and liabilities of [Original 
Monsanto’s chemical products] business.”  Id.  Pharmacia “operates Original Monsanto’s 
pharmaceutical business.”  Id. 
42 Id. at A058-59 (the complaint). 
43 Id. at A061. 
44 Id. 
14 
 
steps to actively mislead the public.  The State sought damages for the harm caused 
by PCBs and the cost to abate PCB contamination from its lands, waters, and natural 
resources. 
E. 
The Superior Court granted Monsanto’s motion to dismiss the complaint.45  
The court found that Delaware does not recognize product-based public nuisance 
claims, and that Monsanto could not be liable for environmental contamination 
under public nuisance and trespass because it did not exercise control over the PCBs 
once sold to third parties.  For the trespass claim, the court found that the State did 
not have standing.  As the court reasoned, although the State had regulatory control 
over the land and resources, the State does not have exclusive possession of lands 
and waters it holds in trust for Delaware citizens.  Finally, the court dismissed the 
State’s unjust enrichment claim because it lacked jurisdiction to hear unjust 
enrichment as a standalone legal claim.  It also concluded that an unjust enrichment 
claim does not extend to future obligations, which in this case arose after 1977 when 
the federal government banned the manufacture and sale of PCBs. 
II. 
Nuisance and trespass are related torts.  In the land use context, a nuisance 
interferes with a plaintiff’s use and enjoyment of property while a trespass interferes 
 
45 State ex rel. Jennings v. Monsanto Co., 2022 WL 2663220 (Del. Super. July 11, 2022). 
15 
 
with a plaintiff’s exclusive possession of property.46  Nuisance is further divided into 
private and public nuisance.  A private nuisance is, like the name suggests, an 
unreasonable interference with a private right.47  A public nuisance is “an 
unreasonable interference with a right common to the general public.”48  Nuisance 
claims overlap with trespass claims when the trespasser physically enters a property 
and, while on the property, engages in activity that affects the possessor’s use and 
enjoyment of that property.49 
Monsanto does not challenge the State’s standing to bring a public nuisance 
claim for the release of PCBs onto Delaware’s lands and into its waters.  Also, it 
does not contest the sufficiency of the State’s pleading that the discharge of PCBs 
onto Delaware’s lands and into its waters is an unreasonable interference with a right 
common to the general public and therefore is a public nuisance.  There is no dispute 
that these circumstances would be sufficient to support a claim of public nuisance 
were it alleged that Monsanto dumped PCBs onto State lands and into State 
waterways directly.  But that is not what happened here.  Rather, Monsanto 
 
46 Page Keeton, Trespass, Nuisance, and Strict Liability, 59 Colum. L. Rev. 457, 464-66 (1959). 
47 Patton v. Simone, 626 A.2d 844, 855 n.8 (Del. Super. 1992) (quoting Restatement (Second) of 
Torts § 821D (1979)). 
48 Id. (quoting Restatement (Second) of Torts § 821B).   
49 Restatement (Second) Torts § 821D cmt. e (“[I]nvasion of the possession of land normally 
involves some degree of interference with its use and enjoyment and this is true particularly when 
some harm is inflicted upon the land itself.”). 
16 
 
manufactured PCBs and sold them to third parties before the PCBs entered the 
environment.   
Focusing on Monsanto’s status as a manufacturer, the Superior Court held that 
Monsanto can avoid addressing the harm caused by its product to a public right 
because under Delaware law “product claims are not encompassed within the public 
nuisance doctrine,” and “[Monsanto] is not liable for public nuisance unless it 
exercises control over the instrumentality that caused the nuisance at the time of the 
nuisance.”50  The State responds that the trial court erred in both findings, because 
Delaware law does not categorically bar product-based public nuisance claims and 
does not impose control as a separate element of a public nuisance claim. 
On appeal we review de novo the Superior Court’s dismissal of a complaint 
under Superior Court Civil Rule 12(b)(6).51  Like the Superior Court, the Supreme 
Court must accept as true all well-pled factual allegations that provide the opposing 
party notice of the claim, draw all reasonable inferences in favor of the plaintiff, and 
determine whether the plaintiff would be entitled to recovery “under any reasonably 
conceivable set of circumstances.”52 
 
 
 
50 State ex rel. Jennings, 2022 WL 2663220, at *2-*4. 
51 Central Mortg. Co., 27 A.3d at 535. 
52 Id. 
17 
 
A. 
Delaware courts have applied the common-sense notion that public nuisance 
liability extends not just to those who own the land, but also to those who 
substantially participate in creating the public nuisance.  For instance, in Keeley v. 
Manor Park Apts., Sec. 1, Inc,53  the plaintiff landowner sued for a drainage problem 
emanating from an adjoining subdivision.  Two of the defendants moved for 
summary judgment and claimed that, after they sold the subdivision, “they did not 
construct or aid in the construction of the streets, spillway and underground conduits, 
and were not legally responsible for any damage to plaintiffs arising therefrom.”54   
The court noted that “[o]ne who erects a nuisance will sometimes be liable for 
its continuance after he has parted with the possession of the land, particularly where 
he conveys the property with covenants for the continuance of the nuisance or 
otherwise derives benefit therefrom.”55  Further, according to the court, “[a]ll those 
who participate in the creation or maintenance of a nuisance are generally liable to 
third persons for injuries suffered therefrom.”56  The court denied the defendants 
summary judgment on the nuisance claim based on disputed issues of material fact 
about their contribution to the nuisance.  It found that, in addition to the fact that the 
 
53 99 A.2d 248 (Del. Ch. 1953). 
54 Id. at 249. 
55 Id. at 250. 
56 Id. 
18 
 
defendants were the original owners of the tract, they designed the lots and the streets 
and their grades.  They also supervised conduit placement and reserved the right to 
use it themselves. 
Another decision illustrating this common-sense approach came thirty-two 
years later, in Hazlett v. Fletcher.57  The defendants no longer owned or controlled 
the property creating the nuisance.  Relying on the Restatement (Second) of Torts, 
the Court of Chancery refused to dismiss a nuisance claim.  It reasoned that “where 
a person participates to a substantial degree in creating a physical condition that is, 
itself, harmful after the activity that created it has ceased, such person generally will 
be subject to continuing liability for future harm.”58  Whether the defendants 
substantially participated in the creation of the nuisance was a question that could 
not be resolved on a motion to dismiss.59 
Although the Court of Chancery’s Keeley and Hazlett decisions show that 
there is no “product based” or “control” exception to nuisance claims under 
Delaware law, the Superior Court drew primarily from Sills v. Smith & Wesson 
 
57 1985 WL 149636, at *2 (Del. Ch. Mar. 1, 1985). 
58 Id.  
59 Id.  More recently, in Robinson v. Oakwood Vill., LLC, 2017 WL 1548549 (Del. Ch. Apr. 28, 
2017), the Court of Chancery entered judgment following trial in favor of the defendants because 
they did not own or control the property.  But the court distinguished Keely and Hazlett by noting 
that “insufficient evidence [existed] on which to extend liability beyond the fee owner during the 
periods relevant to trespass and nuisance liability.”  Id. at *16 n.219.         
19 
 
Corp.,60 State ex rel. Jennings v. Purdue Pharma L.P.,61 and Patton v. Simone.62  
Sills involved negligence and public nuisance claims brought by the City of 
Wilmington against gun manufacturers and others stemming from gun violence in 
Wilmington.  The court observed that Delaware law includes “no express authority 
[] requiring public nuisance claims be restricted to those based on land use,” but the 
court also stated without a supporting citation that “Delaware courts remain hesitant 
to expand public nuisance” to include product-based claims.63  The court ultimately 
avoided the issue, holding that the City failed to state an “independent claim for 
public nuisance” because the public nuisance claims were subsumed in the City’s 
negligence claims.64   
Purdue Pharma involved public nuisance claims brought by the State against 
opioid manufacturers, distributors, and pharmacies stemming from the opioid 
epidemic.  The Superior Court dismissed the State’s claims and held that “[a] 
defendant is not liable for public nuisance unless it exercises control over the 
instrumentality that caused the nuisance at the time of the nuisance.”65  In reaching 
this conclusion, the court relied foremost on the Sills court’s description of Delaware 
courts as “hesitant” to recognize product-based public nuisance claims.  The court 
 
60 2000 WL 33113806 (Del. Super. Dec. 1, 2000). 
61 2019 WL 446382 (Del. Super. Feb. 4, 2019). 
62 1992 WL 398478 (Del. Super. Dec. 14, 1992); 1992 WL 183064 (Del. Super. June 25, 1992). 
63 Sills, 2000 WL 33113806, at *7. 
64 Id. 
65 Purdue Pharma, 2019 WL 446382, at *13. 
20 
 
also relied on Patton, where the court held in early summary judgment decisions that 
one must own or control the property to be liable for public nuisance.66  But in a later 
decision in the same series of cases, the Patton court ruled consistent with 
Delaware’s substantial-participation approach that a defendant “would not be liable 
as it did not carry on the activity which created the nuisance nor assist in carrying it 
out.”67  
B. 
After reviewing the Restatement and the Delaware cases, we conclude that the 
State has stated a claim for public nuisance.  At the outset, we are not persuaded, as 
the Superior Court found, that “product claims are not encompassed within the 
public nuisance doctrine.”68  The most that can be gleaned from Sills and Purdue 
Pharma is that the statement in both cases about a “hesitancy” to recognize product-
based public nuisance claims was unsupported.  In Patton, the court specifically 
recognized that those who assist in carrying on a nuisance can be liable for 
nuisance.69  Further, historical examples abound of products that were held to create 
 
66 1992 WL 398478, at *9; 1992 WL 183064, at *13. 
67 1993 WL 54462, at *13 (Del. Super. Jan. 28, 1993) (emphasis added). 
68 State ex rel. Jennings, 2022 WL 2663220, at *4. 
69 1993 WL 54462, at *13. 
21 
 
a public nuisance.70  Those same cases do not support the notion that a defendant 
must have “control of its product at the time of the alleged nuisance.”71   
The issue, therefore, is not whether a product is involved or whether the 
defendant exercised control of the product at the time of the alleged nuisance.  
Instead, the crux of the issue is: can a product manufacturer be held liable after a 
product it manufactures is sold to third parties whose activities release the product 
into the environment and cause a public nuisance?  For the environmental-based 
public nuisance claim before us, Monsanto can be held liable when it substantially 
contributed to a public nuisance by misleading the public and selling a product it 
knew would eventually cause a safety hazard and end up contaminating the 
environment for generations when used by industry and consumers.  
First, under the Restatement (Second) of Torts, a nuisance causing activity 
includes “all acts that are a cause of harm.”72  The Second Restatement also provides 
that a defendant is liable for nuisance “not only when he carries on the activity but 
 
70 Examples of product-based public nuisance in the Second Restatement include explosives and 
fireworks.  Restatement (Second) of Torts § 821B cmt. b.  See also Leslie Kendrick, The Perils 
and Promise of Public Nuisance, 132 Yale L.J. 702, 738-39 (2023) (“[W]ritings such as 
Sheppard’s and Blackstone’s give the lie to the common assertion . . . that public nuisance 
pertained only to the use of the land.  Several of Sheppard’s and Blackstone’s examples are not 
land-based, including setting off fireworks, being an eavesdropper, and being a common scold[,] 
[a]nd . . . ‘victuallers, butchers, bakers, cooks, brewers, maltsters and apothecaries who sell 
products unfit for human consumption.’”) (internal footnotes omitted); Craven v. Fifth Ward 
Republican Club, Inc., 146 A.2d 400 (Del. Ch. 1958) (entering a preliminary restraining order to 
enjoin, as a public nuisance, the illegal sale of alcohol). 
71 Answering Br. at 4. 
72 Restatement (Second) of Torts § 834 cmt. b. 
22 
 
also when he participates to a substantial extent in carrying it on.”73  As alleged in 
the complaint, continuing to supply PCBs, which were known to be toxic to humans 
and wildlife, to industry and to consumers, knowing PCBs would escape and 
permanently contaminate Delaware’s lands and waters, and taking affirmative steps 
to mislead the public and government officials about the safety of PCBs, qualifies 
as participating to a substantial extent in carrying on a public nuisance. 
It bears noting that comment “g” to Section 8 of the Restatement (Third) of 
Torts states that it excludes from economic loss nuisance liability for products like 
handguns, opioids, and tobacco.74  This decision does not reach the question whether 
Delaware law categorically forecloses nuisance claims against manufacturers of 
products like handguns, opioids, and tobacco for harms caused by those products to 
a public right.  It is sufficient for present purposes to say that comment “g” does not 
 
73 Id. § 834.  The Delaware courts generally consider the Restatement persuasive authority.  See 
Fox v. Fox, 729 A.2d 825, 828-29 (Del. 1999) (explaining that “[w]e find [the Restatement 
(second)] . . . not only persuasive but promotive of humanitarian goals”); Estate of Tigani, 2016 
WL 593169, *18 (Del. Ch. Feb. 12, 2016) (recognizing that “Delaware courts generally find the 
Restatement of Laws to be persuasive authority on many topics”); Stayton v. Delaware Health 
Corp., 117 A.3d 521, 533-34 (Del. 2015) (explaining that “Delaware has followed the Restatement 
(Second) of Torts in its application of the collateral source rule”); In re Peierls Family Inter Vivos 
Trusts, 77 A.3d 249, 255 (Del. 2013) (explaining that “[w]hen confronted with a choice-of-law 
issue, Delaware courts adhere to the Restatement (Second) of Conflict of Laws”); Falconi v. 
Coombs & Coombs, Inc., 902 A.2d 1094, 1099 (Del. 2006) (explaining that “[i]n the context of 
determining vicarious liability for a tort, this Court has recognized the value of the Restatement 
(Second) of Agency as an aid in deciding whether an individual is an employee or independent 
contractor”). 
74 Restatement (Third) of Torts: Liab. for Econ. Harm § 8 cmt. g (2020). 
23 
 
target products like PCBs that cause environmental harm, as reflected in comment 
“a” to that same Section: 
[t]his Section addresses the liability in tort of a defendant who creates 
a public nuisance that results in economic loss to the plaintiff.  This 
Section does not seek to restate the substantive law of public nuisance 
except as necessary to explain those cases that produce liability in tort 
for economic loss alone.  Many public nuisances are not of that 
character; they cause physical harm, as when a defendant negligently 
leaves an obstruction in a road and the plaintiff collides with it, or as 
when a defendant’s pollution causes damage to property that the 
plaintiff owns.  Those cases are outside the scope of this Section.75 
 
The comments to Restatement (Third) of Torts confirm that, for purposes of 
public nuisance, products like handguns, opioids, and cigarettes are not the same as 
products like PCBs that cause environmental harm to property and economic loss to 
the plaintiff. 
Second, as noted earlier, Delaware courts have historically taken a common-
sense approach to the issue.  In the Keeley and Hazlett cases, the trial court 
recognized that, even when the defendant is not a property owner causing the 
nuisance, “where a person participates to a substantial degree in creating a physical 
condition that is, itself, harmful after the activity that created it has ceased, such 
person generally will be subject to continuing liability for future harm.”76  It is 
reasonably conceivable that Monsanto substantially participated in creating the 
 
75 Id. § 8 cmt. a. 
76 Hazlett, 1985 WL 149636, at *2. 
24 
 
public nuisance by selling PCBs to industry and to consumers knowing PCBs would 
escape in the environment and contaminate the State’s lands and waters for 
generations. 
Third, the State joins a long line of government plaintiffs throughout the 
country to assert public nuisance cases against Monsanto for PCB environmental 
contamination, and our view is consistent with almost all those cases.  As those 
courts found, the complaints alleged that Monsanto substantially contributed to a 
public nuisance because it knew for some time that PCBs would cause long-lasting 
environmental harm when used by third parties and hid those dangers from the 
public until forced to cease production.77   
 
77 All but one of the Monsanto PCB cases in other jurisdictions survived motion to dismiss on the 
public nuisance claim.  Abbatiello v. Monsanto Co., 522 F. Supp. 2d 524, 541 (S.D.N.Y. 2007) 
(denying Monsanto’s motion to dismiss because the plaintiffs sufficiently pled that Monsanto 
substantially participated in creating the nuisance by alleging that Monsanto manufactured and 
sold the PCBs to General Electric Company and concealed the dangers of PCBs from General 
Electric Company); City of Spokane v. Monsanto Co., 2016 WL 6275164, at *8 (E.D. Wa. Oct. 
26, 2016) (denying Monsanto’s motion to dismiss because the plaintiff alleged that the PCBs 
migrated into the river even when, and regardless of whether, products containing PCBs were used 
or disposed of as intended (widespread use), and Monsanto knew that widespread use of the PCBs 
it manufactured was contaminating the environment); City of San Jose v. Monsanto Co., 231 F. 
Supp. 3d 357, 363 (N.D. Cal. 2017) (denying Monsanto’s motion to dismiss because the plaintiff 
sufficiently pled that “Monsanto knew that PCBs were dangerous, concealed that knowledge, 
promoted the use of PCBs in a range of applications, and gave disposal instructions that were likely 
to cause environmental contamination”); City of Seattle v. Monsanto Co., 237 F. Supp. 3d 1096, 
1106–07 (W.D. Wash. 2017) (denying Monsanto’s motion to dismiss because the plaintiff 
adequately pled that Monsanto was the sole PCB producer, Monsanto promoted PCBs across many 
different uses/markets, PCBs were the most widespread contaminant in the river, Monsanto knew 
PCBs were dangerous, and Monsanto was on notice in 1960s that PCBs were uncontrollable 
pollutants that endangered the environment as a result of their normal and intended use); Port of 
Portland v. Monsanto Co., 2017 WL 4236561, at *9 (D. Or. Sept. 22, 2017) (denying Monsanto’s 
motion to dismiss because the parties did not sufficiently brief the issue of “whether a plaintiff can 
 
25 
 
For instance, in Mayor & City Council of Baltimore v. Monsanto Co., the 
Maryland District Court denied Monsanto’s motion to dismiss because the City of 
Baltimore “sufficiently alleged that [Monsanto] created or substantially participated 
in the creation of PCBs, even though Defendants may not have maintained control 
over the contaminants once disseminated in the City’s waters.”78  The court relied 
on the allegations that “Monsanto manufactured, distributed, marketed, and 
promoted PCBs, resulting in the creation of a public nuisance that is harmful to 
health and obstructs the free use of the City’s stormwater and other water systems 
 
bring a public nuisance claim for damages when the claim overlaps with a product liability claim”); 
City of Long Beach v. Monsanto Co., 2018 WL 4846657 (C.D. Cal. Aug. 21, 2018) (denying 
Monsanto’s motion to dismiss on other grounds not relevant to this case); County of Los Angeles 
v. Monsanto Co., 2019 WL 13064885, at *10 (C.D. Cal. Nov. 21, 2019) (denying Monsanto’s 
motion to dismiss because the plaintiffs sufficiently pled that “[Monsanto] knew that PCBs were 
toxic as early as the 1930s, and certainly by the 1950s . . . [but] continued to promote the use of 
PCBs in a wide variety of products and downplay the danger of PCBs . . . and instructed its 
customers to dispose of PCB containing wastes in local landfills, knowing that landfills were not 
suitable for PCB-contaminated waste”); Mayor of Baltimore v. Monsanto Co., 2020 WL 1529014, 
at *10 (D. Md. Mar. 31, 2020) (denying Monsanto’s motion to dismiss because the plaintiff 
adequately alleged that Monsanto created or substantially participated in the creation of the PCBs, 
knew about PCBs’ harmful effects, intentionally withheld that information and misrepresented to 
the public and government officials that PCBs were safe, and manufactured and distributed PCBs 
that ended up in Baltimore’s waters, causing harm to humans, animals, and environment); Illinois 
ex rel. Raoul v. Monsanto Co., 2023 WL 3292591, at *3 (N.D. Ill. May 5, 2023) (denying 
Monsanto’s motion to dismiss because Monsanto created or participated in the creation of the 
nuisance by selling PCBs even though it knew PCBs would  “inevitably leach into and pollute the 
State’s natural resources even in the absence of any negligence on the part of the buyer”); 
Commonwealth v. Monsanto Co., 269 A.3d 623, 652 (Pa. Commw. Ct. 2021) (denying Monsanto’s 
motion to dismiss because “Plaintiffs clearly declare that [Monsanto] [is] responsible for PCBs 
entering the Commonwealth’s waters because [Monsanto] knew that the uses for which they 
marketed, sold, and distributed PCB mixtures would result in leaching, leaking, and escaping their 
intended applications and contaminating (i.e., polluting) those waters”); but see Town of Westport 
v. Monsanto Co., 2015 WL 1321466, at *4 (D. Mass. Mar. 24, 2015) (granting Monsanto’s motion 
to dismiss because Monsanto did not have control of the PCB containing products). 
78 2020 WL 1529014, at *10. 
26 
 
and waters.”79  It noted further that Monsanto had knowledge of the harmful effects 
of PCBs and intentionally withheld that information and made misrepresentations to 
the public and government officials. 
Here, the State has pled sufficiently that Monsanto, as the sole PCB producer, 
substantially participated in the creation of the public nuisance.  It alleged that 
Monsanto knew early on about the dangers of PCBs.  In 1937, an internal 
memorandum reported that “[e]xperimental work in animals show[ed] that 
prolonged exposure to Aroclor vapors evolved at high temperatures or by repeated 
oral ingestion will lead to systemic toxic effects.”80  The next year, a Harvard 
professor presented her findings to Monsanto on the toxic effects of PCBs.  In 1953, 
Monsanto’s manager of environmental health drafted an internal memorandum that 
advised that PCBs could not be considered nontoxic.81  Two years later, its chief 
chemist circulated internally an article that reported on the toxicity of PCBs.82  In 
addition to these internal communications, “[t]hroughout the 1940s and 1950s, 
scientists continued to report to Monsanto on the widespread, harmful effects of 
PCBs.”83 
 
79 Id. 
80 App. to Opening Br. at A027. 
81 Id. at A028. 
82 Id. at A029. 
83 Id. at A031. 
27 
 
According to the allegations of the complaint, knowing this information, 
Monsanto took affirmative steps to conceal the toxic nature of PCBs and spread 
misinformation about PCBs negative health effects.  Beginning with its own 
customers, in 1947, it told an inquiring customer that one of its PCB mixtures was 
safe and almost non-toxic.84  It instructed employees to tell customers that systemic 
toxic effects were not significant.85  Its misrepresentations did not stop with 
customers.  In 1957, the U.S. Navy refused to use PCBs in its submarines after it 
conducted an independent test that revealed the toxic nature of PCBs.86  Monsanto 
nevertheless attempted to change the Navy’s mind.   
In 1969, Monsanto also wrote the Los Angeles Air Pollution Control District 
and advised it that PCBs were not toxic either by oral ingestion or skin absorption.87  
It sent a similar letter to the Regional Water Quality Control Board denying any 
special health or environmental problems linked with PCBs.88  Later that year, it 
made similar misrepresentations to the National Air Pollution Control 
Administration and stated that it could not “conceive how the PCBs can be getting 
into the environment in a widespread fashion.”89 
 
84 Id. at A028. 
85 Id. 
86 Id. at A030. 
87 Id. at A043-44. 
88 Id. at A044. 
89 Id. 
28 
 
Monsanto also used a misleading advertisement to conceal the toxic nature of 
PCBs.  In a 1961 brochure, Monsanto promoted PCBs as being widely used in 
household items.90  By 1970, however, it sought to distance itself from its earlier 
promotion.  In a press release, it stated that PCBs were “primarily for use as a coolant 
in electrical transformers and capacitors . . . [and] not [for use as] a ‘household’ 
item.”91  Nevertheless, it continued to market and to sell PCBs for use in household 
items.  Monsanto went as far as establishing a committee and tasking it with 
“preparing recommendations for actions that Monsanto could take to improve its 
reputation and salvage its bottom line.”92  One of the recommendations was to beef 
up the talking points for its employees when discussing the danger of PCBs with 
customers.  
Accepting these allegations as true, as we must at this stage of the 
proceedings, it is reasonably conceivable that Monsanto substantially participated in 
the creation of a public nuisance by manufacturing and selling PCBs that it sold to 
industry and consumers and knew PCBs would eventually end up causing long 
lasting contamination to state lands and waters.  
 
  
 
90 Id at A042. 
91 Id. at A043. 
92 Id. at A037. 
29 
 
III. 
Turning to the State’s trespass claim, the Restatement (Second) of Torts 
provides:  
[o]ne is subject to liability to another for trespass, irrespective of 
whether he thereby causes harm to any legally protected interest of the 
other, if he intentionally 
(a) enters land in the possession of the other, or causes a thing 
or a third person to do so, or 
(b) remains on the land, or 
(c) fails to remove from the land a thing which he is under a 
duty to remove.93 
 
The Superior Court dismissed the State’s trespass claim on two grounds: first, 
the State did not have exclusive possession of lands it holds in public trust; and 
second, Monsanto did not control the PCBs trespassing on the State’s land.   
On appeal, the State argues that it has exclusive possession of land it holds 
directly and also in public trust because the State has the right to exclude unwanted 
persons or objects.  And it contends that the disposition of the control issue for public 
nuisance dictates the result for its trespass claim.      
 
 
 
 
93 Restatement (Second) of Torts § 158 (1965).  See Amer v. NVF Co., 1994 WL 279981, *3 (Del. 
Ch. June 15, 1994) (citing Restatement (Second) of Torts § 158 (1965)) (“A prima facie case of 
trespass is established when plaintiff shows that defendant intentionally and without consent 
entered onto real property belonging to the plaintiff.”). 
30 
 
A. 
Subaqueous lands are held by the State in trust for the public.94  Section 157 
of the Restatement (Second) of Torts defines possession, for the purposes of trespass, 
as one who:  
(a) is in occupancy of land with intent to control it, or (b) has been but 
no longer is in occupancy of land with intent to control it, if, after he 
has ceased his occupancy without abandoning the land, no other person 
has obtained possession as stated in Clause (a), or (c) has the right as 
against all persons to immediate occupancy of land, if no other person 
is in possession as stated in Clauses (a) and (b).95 
The Second Restatement defines “occupancy” as “acts done upon the land as 
manifest a claim of exclusive control of the land, and indicate to the public that he 
who has done them has appropriated it.”96  The Second Restatement also states that 
“[t]he word ‘intrusion’ is used throughout the Restatement of this Subject to denote 
the fact that the possessor’s interest in the exclusive possession of his land has been 
invaded by the presence of a person or thing upon it without the possessor’s 
consent.”97  Under Delaware law,  “[o]nly a person in possession of the property 
may allege a trespass action.”98    
 
94 See Illinois Cent. R. Co. v. State of Illinois, 146 U.S. 387, 452 (1892); Bailey v. Philadelphia, 
W. & B.R. Co., 1846 WL 726, *1 (Del. June 1846). 
95 Restatement (Second) of Torts § 157. 
96 Id. § 157 cmt. a (emphasis added). 
97 Id. § 158 cmt. c (emphasis added). 
98 Pilots’ Ass’n for Bay & River Delaware v. Lynch, 1992 WL 390697, *3 (Del. Super. Nov. 19, 
1992) (citing Reed v. Dehorty, 1804 WL 234 (Del. Com. May 15, 1804)). 
31 
 
Other jurisdictions applying the Second Restatement have found that a state 
does not have exclusive possession of land it holds in public trust.  For example, in 
New Jersey Department of Environmental Protection v. Hess Corporation, the New 
Jersey Superior Court dismissed a trespass claim brought by the state for 
environmental contamination of the state’s natural resources.99  It held that “[l]and 
in the public trust is held by the State on behalf of a second party, the people.  Such 
land cannot be in ‘exclusive possession’ of the State as the interest created by the 
doctrine is intended to ensure that others have use of the same land.”100  The 
Maryland Federal District Court also “dismiss[ed] the State’s trespass claim to the 
extent it [wa]s based on properties outside of its exclusive possession—i.e., its 
natural waters and the properties of its citizens.”101  Several other jurisdictions, many 
of whom relied on the Second Restatement, have followed suit.102   
Here, the State argues that property it holds in trust is in its exclusive 
possession because it can exclude certain people from the property.103  But the public 
trust doctrine significantly limits the State’s right to exclude others.  At best, the 
 
99 2020 WL 1683180, *6 (N.J. Super. Ct. App. Div. Apr. 7, 2020). 
100 Id. (footnote omitted). 
101 State v. Exxon Mobil Corp., 406 F. Supp. 3d 420, 471 (D. Md. 2019). 
102 See, e.g., New Mexico v. Gen. Elec. Co., 467 F.3d 1223, 1247 n.36 (10th Cir. 2006) (“[T]he 
State as guardian of the public trust has no possessory interest in the sand, gravel, and other 
minerals that make up the aquifer—a necessary requisite to maintaining a trespass action.”). 
103 The State relies on Kane v. NVR, Inc., 2020 WL 3027239 (Del. Ch. June 5, 2020), an order on 
exceptions to a Master’s Report.  In Kane, however, the court did not discuss the exclusive 
possession requirement.  It simply noted that trespass interferes with the plaintiff’s possession of 
land.  Id. at * 6.  
32 
 
State shares possession with the public.  The State admits that it may only “impair 
or take away these public rights for public purposes.”104  In other words, the State’s 
control over the land is non-exclusive and may at times be subordinate to the public’s 
right to travel, hunt, or fish.  We conclude that the State does not have exclusive 
possession of land it holds in trust.  Thus, the Superior Court properly dismissed the 
State’s trespass claim for lands it holds in public trust.105 
B. 
The State also asserts trespass claims for land it holds directly.  The parties 
appear to agree that the State satisfies the exclusive possession requirement for a 
trespass claim as to those lands.  For this category of claims, the parties dispute the 
Superior Court’s holding that a defendant must control the intruding instrumentality 
at the time of the trespass. 
To state a trespass claim against a non-landowner for environmental harm, 
“[i]t is enough that an act is done with knowledge that it will to a substantial 
 
104 Opening Br. at 35 (emphasis added). 
105 Monsanto also argues that the State does not allege damage to its lands.  But the failure to allege 
damages is not fatal to a trespass claim.  Under the Restatement (Second) of Torts § 163, “[o]ne 
who intentionally enters land in the possession of another is subject to liability to the possessor for 
a trespass, although his presence on the land causes no harm to the land, its possessor, or to any 
thing or person in whose security the possessor has a legally protected interest.”  Rather, “[t]he 
fact that the actor knows that his entry is without the consent of the possessor and without any 
other privilege to do so, while not necessary to make him liable, may affect the amount of damages 
recoverable against him, by showing such a complete disregard of the possessor’s legally protected 
interest in the exclusive possession of his land as to justify the imposition of punitive in addition 
to nominal damages for even a harmless trespass, or in addition to compensatory damages for one 
which is harmful.”  Id. § 163 cmt. e.  
33 
 
certainty result in the entry of the foreign matter.”106  In its complaint, the State 
identified two State-owned facilities that are located on a former military base the 
State purchased in 1947.  It also alleged that the facilities are located next to “a 
former landfill in which PCB-containing materials were deposited” and “[b]oth state 
and federal agencies have undertaken cleanup, with the EPA removing PCB-
contaminated soil from the area and DNREC performing treatment to eliminate 
hazardous runoff from the site.”107  It is reasonable to infer from these allegations 
that the two facilities were contaminated by PCBs emanating from the adjoining 
landfill.  At least for the military base property, the State has the requisite exclusive 
possessory interest to assert a trespass claim.  If there are other state-owned 
properties contaminated by PCBs, on remand the State can amend its complaint to 
identify those parcels and plead a trespass claim. 
While Monsanto might not have owned adjoining land or dumped the PCBs 
directly onto the State’s land, as the only manufacturer of PCBs in the United States, 
it substantially contributed to the entry onto the State’s land by supplying PCBs to 
Delaware manufacturers and consumers, knowing that their use would eventually 
trespass onto other lands.  Accepting these allegations as true, the State has pled 
sufficiently a trespass claim for land it owns directly.  
 
106 Restatement (Second) of Torts § 158 cmt. i (emphasis added). 
107 App. to Opening Br. at A055 (the complaint). 
34 
 
IV. 
 
Finally, the State argues that the court erred on two grounds when it dismissed 
its unjust enrichment claim: first, the Superior Court did not have jurisdiction to hear 
an unjust enrichment claim as standalone claim; and, second, the State did not allege 
that Monsanto was “enriched” by avoiding future PCB cleanup expenses.  According 
to the State, the Superior Court has jurisdiction because unjust enrichment is a legal 
as opposed to an equitable claim.  It also contends that Monsanto was enriched by 
the State shouldering the burden of PCB cleanup throughout Delaware. 
A. 
 
Unjust enrichment is “the unjust retention of a benefit to the loss of another, 
or the retention of money or property against the fundamental principles of justice 
or equity and good conscience.”108  An unjust enrichment claim can be brought as a 
standalone claim or as a remedy for other claims, like nuisance and trespass.109   
 
108 Fleer Corp. v. Topps Chewing Gum, Inc., 539 A.2d 1060, 1062 (Del. 1988) (quoting 66 Am. 
Jur. 2d Restitution and Implied Contracts § 3 (1973)); Schock v. Nash, 732 A.2d 217, 232 (Del. 
1999) (quoting same). 
109 Garfield on behalf of ODP Corp. v. Allen, 277 A.3d 296, 341 (Del. Ch. 2022) (quoting Dan B. 
Dobbs, Law of Remedies: Damages—Equity—Restitution § 4.1(1), at 366 (2d ed. 1993)).  See also 
Eric J. Konopka, Hey, That’s Cheating! The Misuse of the Irreparable Injury Rule as a Shortcut 
to Preclude Unjust-Enrichment Claims, 114 Colum. L. Rev. 2045, 2054 (2015) (“When discussing 
restitution and unjust enrichment, many authors refer to the ‘substantive’ side and the ‘remedial’ 
side of the phrase.  Substantive unjust enrichment deals with whether, given the facts of the case, 
the plaintiff can establish a viable unjust-enrichment claim.  The remedial component concerns 
what relief is granted for the violation of the substantive right.”). 
35 
 
 
The Superior Court found that “[u]njust enrichment is an equitable claim” and 
therefore could not be heard in the Superior Court.110  In reaching this conclusion, 
the trial court applied the holding of two Superior Court decisions that found that 
unjust enrichment cannot be brought as a standalone claim in Superior Court.111  
Those decisions, however, reflect the confusion caused by one of the elements of an 
unjust enrichment claim – the absence of an adequate remedy at law.   
 
As traditionally articulated by Delaware courts, to support a standalone claim 
for unjust enrichment, a plaintiff must plead: (1) an enrichment; (2) an 
impoverishment; (3) a relation between the enrichment and the impoverishment; (4) 
the absence of justification; and (5) the absence of a remedy provided by law.112  In 
Garfield, however, Vice Chancellor Laster thoroughly explored the provenance of 
an unjust enrichment claim.113  We need not repeat that detailed analysis here except 
to say that, as this Court concluded in Crosse v. BCBSD, Inc., unjust enrichment is 
historically a legal, not an equitable, claim.114  The absence of an adequate remedy 
 
110 State ex rel. Jennings, 2022 WL 2663220, at *6. 
111 Purdue Pharma, 2019 WL 446382, at *14; Incyte Corp. v. Flexus Biosciences, Inc., 2017 WL 
7803923, at *3-*4 (Del. Super. Nov. 1, 2017).  In Incyte, the Superior Court found it did not have 
jurisdiction over the unjust enrichment claim because the dispute was subject to arbitration.  The 
quote from the decision that the Superior Court relied on – “unjust enrichment may be considered 
as part of damages if liability is found but it does not survive as a standalone claim” – referred to 
the fact that the Delaware Uniform Trade Secrets Act displaced the unjust enrichment claim, and 
not that the court lacked jurisdiction to hear the claim.  Id. at *3. 
112 Nemec v. Schrader, 991 A.2d 1120, 1130 (Del. 2010). 
113 Garfield, 277 A.3d at 347-51. 
114 836 A.2d 492, 496-97 (Del. 2003) (explaining that an unjust enrichment claim is an “off-the-
contract theory of recovery” and is a legal, not an equitable claim). 
36 
 
at law is required only if an unjust enrichment claim is brought in the Court of 
Chancery and there is no other independent basis for equitable jurisdiction.115  The 
Superior Court had jurisdiction to consider the State’s standalone unjust enrichment 
claim.    
B. 
The Superior Court dismissed the State’s unjust enrichment claim on the 
alternative ground that the State did not plead that Monsanto was enriched.  
Although the State pled that Monsanto was relieved of paying for cleanup expenses 
through the State’s use of taxpayer money, the court held that “there is no Delaware 
authority supporting the proposition that relief from future obligations amounts to a 
claim for unjust enrichment.”116  On appeal the State argues that “Monsanto has been 
enriched by virtue of being able to walk away from the environmental contamination 
it created, while the State, and Delawareans, shoulder the burden of cleaning up 
Monsanto’s PCBs throughout Delaware.”117 
Under the Restatement (Third) of Unjust Enrichment and Restitution:  
(1) A person who performs another’s duty to a third person or to the 
public is entitled to restitution from the other as necessary to prevent 
 
115 Garfield, 277 A.3d at 351 (“If a plaintiff seeks to pursue a claim for unjust enrichment in the 
Court of Chancery and has no other basis for equitable jurisdiction, then the plaintiff must establish 
the absence of a remedy at law to establish equitable jurisdiction.  Colloquially speaking, the 
absence of a remedy at law can be viewed as an element of the claim.  Outside of a dispute over 
jurisdiction, however, it is not necessary for a plaintiff to plead or later prove the absence of an 
adequate remedy at law.”). 
116 State ex rel. Jennings, 2022 WL 2663220, at *7. 
117 Opening Br. at 45. 
37 
 
unjust enrichment, if the circumstances justify the decision to intervene 
without request. 
(2) Unrequested intervention may be justified in the following 
circumstances: 
(a) the claimant may be justified in paying another’s money 
debt if there is no prejudice to the obligor in substituting a 
liability in restitution for the original obligation; 
(b) the claimant may be justified in performing another’s duty 
to furnish necessaries to a third person, to avoid imminent harm 
to the interests of the third person; and 
(c) the claimant may be justified in performing another’s duty 
to the public, if performance is urgently required for the 
protection of public health, safety, or general welfare. 
(3) There is no unjust enrichment and no claim in restitution by the rule 
of this section except insofar as the claimant’s intervention has relieved 
the defendant of an otherwise enforceable obligation.118 
 
As the Restatement provides, “unrequested intervention” – which is the case 
here – does not typically result in an enrichment unless done under subsection (2)(c) 
to remedy an emergency or under (3) for a pre-existing duty that is not being 
performed by the defendant.  Neither applies here.  First, the emergency exception 
has typically been applied when there is an urgent and immediate need to abate a 
harm.  While few would doubt that PCB contamination is a threat to the public 
health, the situation here is not emergent in that it is time-sensitive like a tanker truck 
spilling its contents along the highway that causes immediate environmental 
 
118 Restatement (Third) of Restitution and Unjust Enrichment § 22 (2011). 
38 
 
contamination.  PCB environmental contamination is serious but not necessarily 
time-sensitive; unfortunately, it has persisted for decades.119     
Second, other than through tort liability, the State has not directed us to “an 
otherwise enforceable obligation” imposed on Monsanto to pay for the State’s 
remediation efforts.  The State cites two cases for the proposition that unjust 
enrichment claims apply “in the context of a public entity undertaking pollution 
abatement costs,”120 but one case involved an explicit statutory duty,121 and the other 
did not address whether the claim for unjust enrichment was viewed as a remedy for 
a tort or a standalone claim.122  As noted earlier, unjust enrichment can be part of the 
State’s remedy under public nuisance and trespass.  As a standalone claim, however, 
it fails. 
V. 
We affirm the Superior Court’s ruling that the State failed to state a claim for 
unjust enrichment and for trespass to lands that the State holds in public trust, but 
 
119 Id. § 22 cmt. h. See, e.g., City of Jacksonville v. Sohn, 616 So. 2d 1173, 1175 (Fla. Dist. Ct. 
App. 1993) (holding that the City of Jacksonville could not maintain an action for the cost of 
abating nuisance conditions because “the City has in no way alleged that it was acting under an 
emergency when it abated the nuisances on appellee’s properties”); Wyandotte Transport Co. v. 
United States, 389 U.S. 191, 204 (1967) (holding that “the [relevant] facts surrounding that 
sinking. . . constitute a classic case in which rapid removal by someone was essential”). 
120 Opening Br. at 46. 
121 See State v. Schenectady Chems., Inc., 479 N.Y.S.2d 1010, 1014 (N.Y. App. Div. 1984) (state 
law imposed a duty upon polluters to abate the pollution). 
122 App. to Opening Br. at A149–50 (The State of Ohio v. Monsanto Co. et al., No. A1801237 
(Ohio Com. Pl. Sept. 19, 2018)) (denying Monsanto’s motion to dismiss a claim for unjust 
enrichment where the court had also denied the motion as to the public nuisance and trespass 
claims). 
39 
 
we reverse its ruling that the State failed to state a claim for public nuisance and for 
trespass to lands that the State owns directly.  The case is remanded to the Superior 
Court for further proceedings consistent with this opinion.