[hippich]

Well, you can't fork, slap different logo, put lower price and compete with oauth.io. So yeah, not what you have in mind.

But on the other hand, this license is no different than GPLv3 except being made for SaaS-type of projects.

[e12e]

Of course you can. But if you do, you have to make your changes available to your users. As oauth.io is already giving away the source code, you'd even be competing on equal(ish) terms.