You can run z/OS just fine on Hercules (mainframe emulator) but IBM does not allow it, and for this reason no one does it.

Given the potential profit in providing emulated z/OS hardware, the fact that no one provides this is quite telling.

Hercules is an interesting case because it's widely rumored to be used inside IBM to run modern System Z releases.

In this case however the company in question isn't just making and selling an emulator you can run iOS on, its selling hosted iOS as a service, which is a clear license violation - just making the emulator and instructions for use available for sale would be quite legal.

Let's say someone ran a service to help you hack AirBNB. Legal?

Let's say someone ran a service which spun up Windows Virtual Machines, of any model, which were not genuine licenses, for the sake of "security research." Legal?

Let's say someone ran a service which helped you find bugs in anti-cheat software and run those bugs on your PC. Legal?

Etc. It's tough.

Microsoft outright encourages this. From https://developer.microsoft.com/en-us/microsoft-edge/tools/v...:

Before installing, please note:

These virtual machines expire after 90 days. We recommend setting a snapshot when you first install the virtual machine which you can roll back to later.

Edit: Furthermore:

The Microsoft Software License Terms for the Microsoft Edge and IE VMs are included in the release notes[1] and supersede any conflicting Windows license terms included in the VMs. By downloading and using this software, you agree to these license terms.

[1]: https://az792536.vo.msecnd.net/vms/release_notes_license_ter...

From the license:

NO ACTIVATION. To prevent its unlicensed use, the software contains activation enforcement technology. Because the software is licensed for testing use only, you are not licensed to activate the software for any purpose even if it prompts you to do so.

Not only are you encouraged to use the software without paying for a license for testing purposes, you're outright forbidden from doing so.

Microsoft are definitely not 'someone' in the sense OP intended.

Let's say someone ran a service which spun up Windows Virtual Machines, of any model, which were not genuine licenses, for the sake of "security research." Legal?

Here, I see "someone" as a security researcher, not someone who is reselling the VMs. The OP may have meant someone spinning them up to resell them to security researchers, but, given the ambiguity, I do think it's important to point out that you can spin up free Windows VMs for research purposes--you are explicitly licensed to do so.

If the analogy is taken literally, then the answer is: yes, it's legal as long as you're not reselling them.

But MS does not encourage you to sell access to those unlicensed copies. Corellium's business model isn't security research, it's taking illegal copies and "renting" them out to people for money. And people go to them because it's convenient, not because there is no other legal way.

Let's say someone ran a service which spun up Windows Virtual Machines, of any model, which were not genuine licenses, for the sake of "security research." Legal?

You can, in fact, legally spin up arbitrary Windows VMs for security research without a paid license.

If any comparison is to be made here, it should be between Apple's licensing and Microsoft's licensing:

* Microsoft will allow you to use Windows without paying for research purposes; Apple will not.

* Microsoft will allow you to run Windows on hardware purchased from a third party, or even hardware you've made yourself; Apple will not.

* Microsoft goes out of their way to facilitate research with the help of virtualization technology; Apple goes out of their way to impede it.

As a customer of both companies, Apple's approach here really rubs me the wrong way and definitely contributes to my unwillingness to completely embrace the Apple ecosystem.

Edit: To be clear, this part:

These virtual machines expire after 90 days. We recommend setting a snapshot when you first install the virtual machine which you can roll back to later.

If you set a snapshot and roll back to it later, you get another 90 days. Rinse and repeat.

Just because someone gave you the right to use for free something that belongs to them doesn't mean you are allowed to sell that right or that "something", or even pass it on for free.

The analogy is harmful because it implies that it's unreasonable to expect that like Microsoft and Apple would allow their software to be used for free for research purposes; it doesn't mention resale of the software. I don't see that as an unreasonable expectation; Microsoft does it without issue.

Edit: Just to be clear, Microsoft is not offering these VMs as a service. You are required to download the image and run it yourself. It’s basically just a license to use Windows for free as long as it’s for a specific kind of research.