IANAL but if someone makes code publicly available (for 3 years). Then isn't there an argument to be made that its reasonable to make use of it? Probably not redistribute it, but use it at least. So I'm not even sure an explicit upload license would be required.
You seem to be arguing for an implied license; such things do exist—but the exact scope is often not obvious even to lawyers in the absence of case law covering very similar situations as to the kind of content and the use to be made of it.
If you leave your keys in your car for 3 years it's still illegal for me to take a joy ride in it. I don't personally believe in/support the concept of IP but in a world that does (like the US) it doesn't make sense to me that people being able to see your property for 3 years gives them the right to use it.
Actually, in the US "Abandoned Vehicle" is a legal thing and depending on local laws you might very well be able to claim, and get title to a vehicle that has been abandoned on your property. And the abandonment period can be really short, 48 hrs in some states. It depends on your state's definition of "abandoned vehicle", and local laws, and it will probably require a few trips to the DMV and might require filing in small claims court, but there is a legal process for gaining ownership of a vehicle that has been left on your property.
Same for any lost property, if you find something valuable (wallet full of cash), you generally have to turn it in to the police, and there is a notification process to try to find the owner, and after a period of time (generally 3 months), if no one has claimed it, it's yours. Again, local laws are going to differ, but the general legal concept, that "A finder of property acquires no rights in mislaid property, is entitled to possession of lost property against everyone except the true owner, and is entitled to keep abandoned property."[1] is common.
There's some old saying about possession being 9/10ths of the law....
I have never ever seen a sign next to the mints saying they a free for patrons. I just assume because that's the done thing, I would make the same presumption about the software package.
Of someone leaves a car on my drive I can do something about it, you may not be able to do in your territory. I'm surprised there isn't the a legal concept of abandonment though, what do you do if someone drops an empty can on your land?
With physical property, there is the concept of Squatter's Rights. With copyright, if you fail to protect it adequately (which I don't think is very well defined by the court system), then the IP in question can pass into the public domain.
I'm not sure what all rights (physical or otherwise) might be applicable here.
> With copyright, if you fail to protect it adequately (which I don't think is very well defined by the court system), then the IP in question can pass into the public domain.
This is not true. Not even remotely true. It is routine that a company notices someone using their copyrights after decades and then sues about it. Oracle is suing Google over code that was "unprotected" for a decade before they decided to sue. In Australia (I know, different country, but this is the same), Men at Work were successfully sued 29 years after they released "Land Downunder" because it has a two bar riff with similarity to a song written in 1928 [1].
As a side note, I see this all the time. What is it about this particular topic that people seem to (a) consistently confuse these things but more importantly (b) feel confident enough about ti to repeat the confused viewpoint with certainty to others?