UNITED STATES COURT OF APPEALS 

FOR THE TENTH CIRCUIT 

_________________________________ 

MARCY BRITTON, 

 Plaintiff - Appellant, 

v. 

MAYOR TIM KELLER; DANNY 

NEVAREZ; CITY OF ALBUQUERQUE, 

 Defendants - Appellees. 

No. 20-2054 

(D.C. No. 1:19-CV-01113-KWR-JHR) 

(D. New Mexico) 

_________________________________ 

ORDER AND JUDGMENT*

_________________________________ 

Before MATHESON, Circuit Judge, LUCERO, Senior Circuit Judge, and McHUGH, 

Circuit Judge. 

_________________________________ 

The City of Albuquerque, New Mexico (the “City”), has a “trap, neuter, release” 

(“TNR”) program for feral cats. The program involves catching, vaccinating, and 

sterilizing feral cats, then releasing them. The feral cats are supposed to be released 

where they were caught, but Marcy Britton alleges they are sometimes released 

elsewhere in the city. This, she claims, has resulted in a colony of feral cats on or near her 

property. She sued the City, the mayor of the City, Tim Keller, and the director of the 

*

 This order and judgment is not binding precedent, except under the doctrines of 

law of the case, res judicata, and collateral estoppel. It may be cited, however, for its 

persuasive value consistent with Federal Rule of Appellate Procedure 32.1 and 

Tenth Circuit Rule 32.1. 

FILED 

United States Court of Appeals 

Tenth Circuit 

March 15, 2021

Christopher M. Wolpert 

Clerk of Court
2 

City’s Animal Welfare Department, Danny Nevarez, under 42 U.S.C. § 1983, alleging 

the TNR program has worked a taking of her property. She also sued under the New 

Mexico Constitution and state tort law. The district court dismissed her operative, 

amended complaint, holding (1) the TNR program could not constitute a taking as a 

matter of law; (2) Ms. Britton had not alleged sufficient facts to demonstrate a taking 

even if it could; and alternatively holding (3) the individual defendants were entitled to 

qualified immunity. The district court also declined to exercise supplemental jurisdiction 

over the state law claims. Ms. Britton appeals. Exercising jurisdiction under 28 U.S.C. 

§ 1291, we affirm. 

I. BACKGROUND 

A. Factual History1

The City operates a TNR program by which feral felines are trapped, sterilized, 

and vaccinated. Although they are supposed to be released where originally trapped, cats 

are sometimes released at a “new location unfamiliar to the cat regardless of whether the 

appropriate care or sustenance exists at that location and without regard to impacts to 

property values, or damage to private property.” App. at 7. Mr. Keller “has directed the 

TNR program to continue” and Mr. Nevarez “orders that the cats continue to be 

dumped.” Id.

1

 Because this appeal concerns a motion to dismiss under Federal Rule of Civil 

Procedure 12(b)(6), the facts are those alleged in the operative complaint, which are 

presumed to be true in this procedural posture. See Smallen v. The W. Union Co., 950 

F.3d 1297, 1305 (10th Cir. 2020). 
3 

Ms. Britton has “a real property interest in certain real estate located in the City.” 

Id. at 6. The feral cats were released “in the vicinity of the property in question.” Id. at 

132 (quoting Ms. Britton’s response to the motion to dismiss, id. at 97). The cats then 

established a feral cat colony “residing near, or at times, on, [Ms. Britton’s] property,” 

risking her exposure to diseases carried by the cats as well as damage to her property 

from the cats’ excrement and urine. Id. (quoting id. at 97). The feral cat colony near or on 

Ms. Britton’s property has contained “dozens, if not tens of dozens, of feral cats” over 

time, which enter or soil her property. Id. at 7. On one occasion, a party preparing to 

make an offer to purchase Ms. Britton’s property decided not to do so because of the feral 

cats. Ms. Britton believes the “property will now appraise for less tha[n] she purchased 

[it] for as a result of” the TNR program. Id. at 7–8. 

B. Procedural History 

Ms. Britton filed suit in the United States District Court for the District of New 

Mexico. Her amended complaint contained two counts. In Count I, brought under 42 

U.S.C. § 1983, she alleged the TNR program worked a taking of her property in violation 

of the United States Constitution. Ms. Britton also argued in Count I that this conduct 

violated the New Mexico Constitution. In Count II, she alleged trespass and nuisance 

under New Mexico tort law. The City moved to dismiss pursuant to Federal Rule of Civil 

Procedure 12(b)(6).2

 It argued Ms. Britton had not alleged facts sufficient to show a 

2

 All relevant documents were jointly filed by the three defendants. We attribute 

arguments common to all defendants to the City. 
4 

violation of the Takings Clause or to show the individual defendants were liable 

personally for the violation, and that the individual defendants were entitled to qualified 

immunity. It also argued the state law claims should be dismissed on sovereign immunity 

grounds and because the facts were insufficient to show a nuisance. Ms. Britton opposed 

the motion. 

The district court granted the motion to dismiss. It held “feral cat colonies do not 

constitute government occupation of [Ms. Britton’s] property,” and the government’s 

actions in administering the TNR program could not legally constitute a taking because 

any injury “was incidental” to the exercise of “police powers” and did not take the 

“property for public use.” Id. at 133–4. Employing the framework of Penn Central 

Transportation Co. v. City of New York, 438 U.S. 104 (1978), the district court 

alternatively held that Ms. Britton’s allegations did not state a plausible regulatory taking 

because “the character of the regulation outweighs any economic impact, even if severe,” 

and that her allegations did not “raise a plausible claim that government actions resulted 

in a reduction in value of her property.” App. at 138. Additionally, the district court held 

the individual defendants were entitled to qualified immunity because Ms. Britton had 

not sufficiently pleaded their personal involvement or shown any constitutional violation 

was clearly established. Finally, the district court declined to exercise supplemental 

jurisdiction over the state law claims. The district court entered judgment dismissing the 

§ 1983 claim with prejudice and the state law claims without prejudice. Ms. Britton 

timely filed a notice of appeal. 
5 

II. DISCUSSION 

We review de novo a district court’s grant of a motion to dismiss, taking as true 

the well-pleaded allegations in the complaint. Smallen v. The W. Union Co., 950 F.3d 

1297, 1305 (10th Cir. 2020). 

A. Legal Background 

The Fifth Amendment to the United States Constitution proscribes taking of 

private property “for public use, without just compensation.” U.S. Const. amend. V; see 

also Alto Eldorado P’ship v. Cnty. of Santa Fe, 634 F.3d 1170, 1173 (10th Cir. 2011) 

(noting that the Takings Clause applies against state and municipal entities via 

incorporation through the Fourteenth Amendment). “The paradigmatic taking requiring 

just compensation is a direct government appropriation or physical invasion of private 

property.” Lingle v. Chevron U.S.A. Inc., 544 U.S. 528, 537 (2005). 

But “[r]egulation of private property may be so onerous that it violates the Takings 

Clause of the Fifth Amendment and requires the government to provide compensation.” 

Ramsey Winch Inc. v. Henry, 555 F.3d 1199, 1208 (10th Cir. 2009). A per se regulatory 

taking occurs where “government requires an owner to suffer a permanent physical 

invasion of her property” or a regulation “completely deprive[s] an owner of ‘all

economically beneficial us[e]’ of her property.” Lingle, 544 U.S. at 538 (quoting Lucas v. 

S.C. Coastal Council, 505 U.S. 1003, 1019 (1992) (emphasis in Lucas, second alteration 

in Lingle)). 

Otherwise, a regulation may create a taking under standards the Supreme Court set 

forth in Penn Central. See Ramsey Winch, 555 F.3d at 1208. “The major factors under the 
6 

Penn Central inquiry are (1) ‘[t]he economic impact of the regulation on the claimant,’ 

(2) ‘the extent to which the regulation has interfered with distinct investment-backed 

expectations,’ and (3) ‘the character of the governmental action.’” Id. at 1210 (quoting 

Penn Cent., 438 U.S. at 124) (alteration in original, italicization added). “The Penn 

Central inquiry focuses on the magnitude of the economic impact of the regulatory action 

and the extent of the regulation’s interference with property rights to determine if the 

regulatory action constitutes a taking.” Alto Eldorado P’ship, 634 F.3d at 1174. 

B. Application 

We first conclude the district court correctly determined feral cats cannot be the 

instrumentality of a government physical occupation for purposes of a paradigmatic 

taking. Because this means Ms. Britton can succeed only if she has properly alleged a 

regulatory taking, we then focus on Ms. Britton’s argument regarding the district court’s 

Penn Central analysis. Ms. Britton argues the district court erred in performing a Penn 

Central analysis on a motion to dismiss. In her view, because the Penn Central analysis 

is fact specific, a district court must wait for the factual development that occurs in 

discovery before undertaking it. Ms. Britton is incorrect. 

Paradigmatic Taking 

A government invasion of property constitutes a paradigmatic taking. Lingle, 544 

U.S. at 537. But our precedent bars Ms. Britton from asserting that the cats themselves 

constitute a physical government invasion on her property. See Mountain States Legal 

Found. v. Hodel, 799 F.2d 1423, 1428 (10th Cir. 1986) (en banc) (rejecting the 

“argument that . . . wild horses are, in effect, instrumentalities of the federal government 
7 

whose presence constitutes a . . . governmental occupation of the Association’s 

property”). While the cats may have entered Ms. Britton’s property, the government did 

not; nor did the government direct the cats to do so. Therefore, we read Ms. Britton’s 

complaint as advancing some species of regulatory taking claim. 

The cases Ms. Britton cites on this point do not help her. She asks us to liken her 

claim to that in Fallini v. United States, 56 F.3d 1378 (Fed. Cir. 1995), but that case 

explicitly relies on our holding in Mountain States that wild horses are not 

instrumentalities of the United States government. Id. at 1383 (holding that the plaintiffs’ 

claim was time-barred because it must have accrued from governmental action—the 

passing of the legislation at issue—not the actions of the horses, who were “not agents of 

the Department of the Interior”). Colvin Cattle Co. v. United States, 468 F.3d 803 (Fed. 

Cir. 2006), the other case Ms. Britton raises, is equally unhelpful. There, the plaintiff—a 

private rancher—sued the United States, claiming the Bureau of Land Management’s 

(BLM) grant of grazing rights to another rancher and its failure to remove wild horses 

from a parcel of public land constituted a taking of the plaintiff’s stockwatering rights on 

that land. Id. at 808–09. In particular, the plaintiff claimed the BLM had failed to prevent 

the other rancher’s domesticated cattle as well as wild horses from infringing on his water 

rights. Id. With respect to the cattle, the Federal Circuit rejected the claim both because 

the United States could not be held responsible for a private rancher’s incursion on the 

plaintiff’s water rights and because the BLM had required that rancher to provide his own 

water. Id. at 809. As for the wild horses, the court held they were “outside the 

government’s control” so “they cannot constitute an instrumentality of the government 
8 

capable of giving rise to a taking.” Id. (citing another Federal Circuit case which cited 

Mountain States). The feral cats here are likewise beyond the City’s control and Colvin 

provides no support for Ms. Britton’s claim.3

To be sure, the City has certain responsibilities related to the feral cats at issue in 

this case. See N.M. Stat. Ann. § 77-1-12 (2009). But Mountain States teaches this sort of 

regulatory authority over certain species does not make those animals instrumentalities of 

the government. 799 F.2d at 1428. There, the claim was that the Secretary of the Interior 

was required to remove wild horses from private lands on request but had failed to do so. 

Id. at 1424–25. We never addressed whether the Secretary was, in fact, acting unlawfully 

in failing to remove the wild horses. We simply determined there had been no taking. Id.

at 1431. We similarly take no position as to whether the City is fulfilling its role under 

New Mexico law through the TNR program. That issue is not before us; the question is 

whether the City has violated the United States Constitution’s Takings Clause, not the 

laws of New Mexico. We hold that it has not. 

3

 We note that Ms. Britton has waived any argument that cats can be distinguished 

from the horses at issue in Mountain States, because cats are traditionally domestic 

animals while the horses were specifically defined by statute as wild. Ms. Britton’s 

opening brief does not use the words “domestic” or “domesticated,” nor does it use the 

term “wild animal” or otherwise suggest the cats are not wild animals. And she does not 

ask us to distinguish Mountain States on this ground. Although Ms. Britton does raise the 

domestic/wild distinction in reply, that is too late. The argument is waived. See United 

States v. Leffler, 942 F.3d 1192, 1197 (10th Cir. 2019) (“In this Circuit, we generally do 

not consider arguments made for the first time on appeal in an appellant’s reply brief and 

deem those arguments waived.”). 
9 

In doing so, we have no reason to—and therefore do not—pass on Ms. Britton’s 

state law claims for trespass and nuisance. Those claims were premised on supplemental 

jurisdiction and the district court properly declined to exercise jurisdiction over them (and 

dismissed them without prejudice) when it determined the federal takings claim could not 

succeed. See Koch v. City of Del City, 660 F.3d 1228, 1248 (10th Cir. 2011) (“When all 

federal claims have been dismissed, the court may, and usually should, decline to 

exercise jurisdiction over any remaining state claims.” (quotation marks omitted)). If the 

TNR program is unlawful under New Mexico law, as Ms. Britton suggests, she may press 

her claims in a court of competent jurisdiction. We hold only that any remedy she may 

have for the City’s alleged violations of N.M. Stat. Ann. § 77-1-12 is not found in the 

Takings Clause of the United States Constitution. 

Regulatory Taking 

At oral argument, Ms. Britton suggested she might be advancing a per se

regulatory taking theory. A per se regulatory taking, however, requires Ms. Britton to 

show either “a permanent physical invasion of her property” or that the regulation 

deprives her of “all economically beneficial use of her property.” Id. at 538 (internal 

quotation marks omitted, first emphasis added). Ms. Britton has not alleged the cats 

permanently occupied her property. Nor has she alleged they deprived it of all 

economically beneficial use. See App. at 7–8 (alleging Ms. Britton’s “property will now 

appraise for less tha[n] she purchased the property for” but not that it is valueless); Oral 

Argument at 1:44–1:54 (agreeing Ms. Britton was not arguing her property was deprived 
10 

of economically beneficial use). She therefore cannot succeed on a per se regulatory 

taking theory.

“[T]he pleading standard Rule 8 announces does not require ‘detailed factual 

allegations,’ but it demands more than an unadorned, the-defendant-unlawfully-harmedme accusation.” Ashcroft v. Iqbal, 556 U.S. 662, 678 (2009) (quoting Bell Atl. Corp. v. 

Twombly, 550 U.S. 544, 555 (2007)). “To survive a motion to dismiss, a complaint must 

contain sufficient factual matter, accepted as true, to ‘state a claim to relief that is 

plausible on its face.’” Llacua v. W. Range Ass’n, 930 F.3d 1161, 1177 (10th Cir. 2019) 

(quoting Iqbal, 556 U.S. at 678). Plausibility requires the plaintiff to plead “factual 

content that allows the court to draw the reasonable inference that the defendant is liable 

for the misconduct alleged.” Brokers’ Choice of Am., Inc. v. NBC Universal, Inc., 757 

F.3d 1125, 1136 (10th Cir. 2014) (quoting Iqbal, 556 U.S. at 678). “This requirement of 

plausibility serves not only to weed out claims that do not (in the absence of additional 

allegations) have a reasonable prospect of success, but also to inform the defendants of 

the actual grounds of the claim against them.” Robbins v. Oklahoma, 519 F.3d 1242, 

1248 (10th Cir. 2008). “The question is whether, if the allegations are true, it is plausible 

and not merely possible that the plaintiff may obtain relief.” Llacua, 930 F.3d at 1177. 

Thus, under the Twombly and Iqbal pleading standard, Ms. Britton needed to plead 

facts sufficient to plausibly suggest she could show a non-per se regulatory taking under 

Penn Central. Further factual development is unnecessary because the allegations in the 

amended complaint are taken to be true. If the factual content in the amended complaint 

does not allow at least a plausible inference that a regulatory taking occurred under Penn 
11 

Central, dismissal is appropriate. See Taylor v. United States, 959 F.3d 1081, 1087 (Fed. 

Cir. 2020) (concluding, in reviewing a motion to dismiss a takings claim, “that the 

[plaintiffs’] regulatory-taking claim cannot pass muster under [the Penn Central] 

standards, even without further factual inquiry”).4

 Simply put, the district court did not 

err in assessing whether Ms. Britton’s factual allegations were sufficient to state a 

regulatory taking claim under the governing legal standard. 

Usually, we would proceed to consider the district court’s analysis of 

Ms. Britton’s amended complaint to determine whether the dismissal was, in fact, 

appropriate. That is unnecessary here, however, because Ms. Britton has forfeited the 

argument that her amended complaint could survive if the district court correctly 

performed the Penn Central analysis at the motion to dismiss phase. To the extent 

Ms. Britton gestures on appeal toward an argument that the district court’s Penn Central 

analysis was wrong rather than merely premature, she does so insufficiently to preserve 

the issue for our review. See Bronson v. Swensen, 500 F.3d 1099, 1104 (10th Cir. 2007) 

(“[W]e routinely have declined to consider arguments that are not raised, or are 

4

 The other circuit courts to have encountered this question, albeit in unpublished 

decisions, are all in agreement that the Penn Central analysis can be conducted at the 

pleading stage. See Sierra Nevada SW Enters., Ltd. v. Douglas County, 506 F. App’x 

663, 666–67 (9th Cir. 2013) (unpublished) (applying the Iqbal pleading standard to a 

takings claim and finding it wanting under Penn Central); Yur-Mar, L.L.C. v. Jefferson 

Par. Council, 451 F. App’x 397, 400–01 (5th Cir. 2011) (unpublished) (same); see also 

Acorn Land, LLC v. Baltimore Cnty., 402 F. App’x 809, 816–17 (4th Cir. 2010) 

(unpublished) (determining the plaintiff had met the Iqbal pleading standard when 

considering the Penn Central factors). We are unaware of any circuit court to have held 

to the contrary, and Ms. Britton does not direct our attention to any such decision. 
12 

inadequately presented, in an appellant’s opening brief.”). Ms. Britton’s opening brief 

contains only one paragraph arguably on this point, consisting of three sentences. She 

argues her amended complaint alleged an unreasonable “interfere[nce] with her property 

interests” through the creation of the feral cat colony; that “the damage and blighting of 

her property” was in line with opening flood gates to release water; and that the district 

court’s decision was therefore wrong. Appellant Br. at 12. At no point does she recite or 

attempt to apply the Penn Central factors. 

And Ms. Britton’s only citation on this point, Arkansas Game & Fish Commission 

v. United States, 568 U.S. 23 (2012), does not help her. There the Supreme Court 

considered a “temporary physical invasion by government.” Id. at 38. The Court 

concluded that temporary flooding could be a taking, but did not conclude such flooding 

necessarily constituted a taking. Id. at 34, 38. Rather, it remanded for consideration of a 

multifactor balancing test applicable to temporary physical invasions, including many of 

the Penn Central factors. Id. at 38–41. Thus, that case establishes only that a balancing 

analysis must be performed even though the invasion is temporary. The district court here 

did perform a Penn Central analysis, so Arkansas Game & Fish Commission is 

inapposite. Ms. Britton has not properly presented for our review any argument that the 

district court’s application of the Penn Central analysis is erroneous. 

Ms. Britton next contends that the facts alleged are not themselves “fantastic,” 

Reply Br. at 5 & n.1 (“Appellant was not making allegations akin to a visit from little 

green men from Mars or adventures in time travel” (citing Iqbal, 556 U.S. at 696 (Souter, 

J., dissenting)), and that the Penn Central standard is fact-intensive. True enough, but 
13 

these points do not show the district court erred in evaluating whether Ms. Britton’s 

amended complaint, taken as true, plausibly showed a regulatory taking.5

 Accordingly, 

her appeal cannot succeed. 

III. CONCLUSION 

We AFFIRM. 

Entered for the Court 

Carolyn B. McHugh 

Circuit Judge 

5

 “When a defendant raises the qualified-immunity defense, the plaintiff must . . . 

establish (1) the defendant violated a federal statutory or constitutional right and (2) the 

right was clearly established at the time of the defendant’s conduct.” Ullery v. Bradley, 

949 F.3d 1282, 1289 (10th Cir. 2020). Because Ms. Britton has not demonstrated the 

district court erred in concluding the TNR program did not implicate the Takings Clause, 

the individual defendants are also entitled to qualified immunity under the first prong of 

that analysis.