If you stealing bitcoin in a country where bitcoin is illegal to use, that's not illegal. It is legal because that country doesn't have responsibility with the crime that can't be prove.

But maybe it is an immoral attitude.

Stealing bitcoins is illegal. Since stealing is considered illegal.
But what you are saying is not stealing since you did not take it from someone it just an accident and also you don't know who owns or how it went there.
Lastly it is impossible to happen and can never occur since there are no duplication of wallets

While I read the topic, I was like 'wtf did I just read  '. Maybe you should make the topic a bit more clear?

Well, if you generate an address and some coins were already there and you use those coins, then it's illegal.

Let's make this even more simple.
Suppose, you generate a private key and somehow it turns out to be the private key of a very large exchange. You transfer those coins to your address. Then the exchange announces that it got hacked and will take legal steps against you. So there you have it, it's illegal

yes, it is legal if it happens like that, but if you intentionally take someone from walletnya bitcoin, it was called a thief and it is clearly illegal. it's the same as taking money in the bank without anyone in mind. of course it was very dangerous and of course the money you get is illegal. maybe you'd better not do that

Of course, stealing is illegal and the closest thing it can harm people who become victims. Theft is a crime that has no sense of social good. Don't ever steal though was in critical condition, look for a better way and does not pose a big problem later on

Yeah stealing any kind of things that without permission of the owner is illegal but in the case of the Op. He/She said that he generate new bitcoin address and received some bitcoin thats not illegal because he/she didnt get it for himself/herself so it is like money that fall in some place and he find it without knowing who is the owner of that money. So in that case it is not stealing .

Yes when u say stealing then yes its illegal.And bitcoin is a currency its also a money so stealing it surely illegal but what you are talking about is don’t think gonna happen.The chance to that happen is very very less.

of course its illegal, not only for bitcoin, but for everything

To generate a new address (having the same private key as someone else) the chances are very low, I was thinking similar to you when i tried to generate new vanity bitcoin addresses, but there are lots of combination that the percentage is very very low. But if you are very lucky then spending these money are illegal, I consider the same as spending money from someone's purse.