As I understand it and having searched for the relevant statute, I cannot find any legislation which specifically limits in clear terms the number of cats or dogs that a citizen of Pennsylvania (PA) can own. The reason is because state legislators don’t want to impose these sorts of property owning restrictions on people. It is too intrusive. I am referring to companion animal domestic cats as I believe that the question is referring to domestic cats.
On the basis that that is correct, it leaves the door open for an individual to own many cats. There is a big caveat, however.
Firstly, there may be county or city ordinances which place restrictions on pet numbers. These are not too uncommon apparently in US cities. You’ll have to check local ordinances.
Also the owner of many cats in PA will have to make sure she or he complies with laws which are not about cats but general areas to do with animal welfare and social cohesion.
For instance, PA’s cruelty to animals laws refers to ‘neglect of animal’ (5532). Clearly if a person has a lot of cats he or she is more likely to neglect the welfare of some or all of the cats. This would be a crime in PA and indirectly it does place a limit on the number of cats a person can own if that person is incapable to caring for many cats. There may be financial reasons underpinning the neglect of the failing health of the person.
There are other animal welfare laws in PA which indirectly impact on the number of cats a person can own. It would be a crime to abandon a cat. If a person had too many cats and abandoned one or two that person would commit a crime. This is another indirect restriction on the number of cats one owns in PA.
Then there is the tort of nuisance. If a person keeps 20 cats and if those cats become a legal nuisance to a close neighbor, that neighbor may be able to apply for an injunction against the cats’ owner to manage their cats better or reduce the number. This is a civil action.
In respect of apartment owners and leasehold houses there will be restrictions on cat and dog ownership under the terms of the lease. This is not specific to PA but it is relevant to the citizens of PA.
Every state in the US will have similar laws to those of PA.
As I recall Florida is one of the few states where there is an express limitation on the number of cats but I can’t find it! I am still searching.
Hope this helps. This is a complicated area, potentially, because the question cuts across several areas of law.
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