What is the legal precedent for taking ownership of a company's assets (without apparently even informing them beforehand) and randomly giving them to some other company to use?
Well, I'll give you an example--which does not apply in this case, but it is an example. Suppose that a company owes you money, suppose they got into that situation by deception (lying about their ability to pay). Suppose further that you discover that they intend to thwart any collection activity by moving their assets out of the country as soon as you go to court to get a judgment, because, say, they tell you exactly that: "if you try to sue us, we'll just move our assets out of the country!"
In that case, you can file for an ex-parte hearing to get a writ of attachment and have the sheriff show up at their offices with a moving van, completely unannounced. Now, the thing is, if you present false information to the court to obtain that order, you have put yourself on the hook for any and all damages you cause to the business by showing up and taking their stuff, so it's really not a wise idea to do this unless they actually owe the money, and you actually have the evidence that they intend to engage in hiding assets from the court.