Lets say Alice Co. writes a program, and Bob Co. hires a contractor to copy it, and put it on their platform?
What is the general legal recourse in these cases? I say general, because most of us are programmers, not lawyers, and we all understand we're not asking for qualified legal advice.
But generally.
What happens? Do you take them to court? What considerations should be taken? What gives you ground to stand on, and others nothing to stand on?
You really need to have a discussion with a lawyer about this. I'm currently listening to the audio version of Bargaining With The Devil. In this book, IBM and Fujitsu were colliding in court and arbitration over copying of source code.
hires a contractor to copy it
All 5 of those are different, and may not be torts in all jurisdictions. The first is usually a criminal matter, #2 may be merely a civil case over violating the license (almost all software licenses have a restriction against reverse engineering), and the third may or may not be a trademark issue. Numbers 3 and 4 might be patent violations, depending on country, patent and decade. And the fifth might be a copyright violation (or depending on how the copy was obtained, perhaps a criminal matter).
The legal system is littered with companies (and lawsuits) that you can look at to give some idea of how messed up things are. For example, SCO was convinced that IBM copied some of the source from Unix to put into Linux - so SCO wanted several billion dollars in damages. Or how Microsoft copied Stac Electronics' source code to place into DOS version 6, and the litigation took long enough that Stac's value as a company dropped to the point where it was cheaper for Microsoft to purchase the company than continue with the lawsuit (I suspect that SCO was also angling to have IBM purchase them, but they forgot that IBM fights legal battles to the death much like Walmart does).
What gives you ground to stand on, and others nothing to stand on?
There are too many variables to even begin to answer this question with anything less than a large book.
Does Bob Co own the right to run it? If so, there's nothing wrong. If not, the contractor should refuse to do the work because it's illegal. But ultimately Bob Co would be legally responsible for the piracy.
Depending on the damages, taking them to court might of course be more expensive than doing nothing. But reporting it to anti-piracy watchdogs can help as those sometimes carry out raids of their own (and a company that pirates one thing can be expected to pirate much more, including stuff from companies that do have the funds to go to court over it).
Bob Go to Jail. Bob Go directly to Jail. Bob Do not pass GO. Bob Do not collect $200.
Source code is intellectual property, and like any property, taking it from its owner is illegal.
The problem is that Alice will have to prove Bob copied her intellectual property.
The answer is copyright. If Alice, Co. produces a program, they presumably have the copyright on it. If Bob, Co. copies it, that's a violation of copyright, and Alice, Co. can sue over that, for damages and an injunction to stop Bob, Co. from further copying.
In the US, damages come in various kinds, but it's normally possible to sue for any harm Bob has done. There are additional things that Alice can ask for if Alice has registered the copyright on the program. (By the Bern Conventions, which most countries have laws conforming to, copyright exists without registration, but in the US there are benefits to registering.) It may or may not be possible to sue to recover legal costs.
The court order to stop doing that may be more important, if that's one of Bob's business strategies.
There are other possibilities I'm even fuzzier on. All disclaimers apply: I am not a lawyer, I don't even know what jurisdiction(s) you're talking about, this is not legal advice, I take responsibility for no consequences of following it, and relying on what I say in court or in other serious legal doings has an excellent chance of getting you what you deserve for something stupid.
