Err, no, in most places in the world. Copyright is very different between nations: book publishers, for example, sell separate rights in geographical regions.
In the UK, you automatically gain copyright for any original work. You don't need to put provisos on your work; protection is just there, unless you provide a copying licence.
A few years ago, you could "establish your copyright" by posting a copy of your work to specified UK libraries and one of the Dublin colleges (the law was not ammended to cope with the idea of an independent Ireland). "Establishing copyright" just means judgement against the copier can be very quick. The publication of private letters has been successfully challenged in UK courts for breach of copyright, and everything is copyright. Even your hand written note to the cleaner.
If a UK software company goes out of business, who knows who owns what? The copyright is an asset and so it depends on who inherits it.