They're not dumping toxic waste, it's just soil dredged up from a nearby area. Not polluted soil, not radioactive soil, just soil. This is not a big deal.
In Australia there is a tax law that states something to the effect of 'If the tax office determines that you're doing something for no other reason than to avoid paying tax, they can deem it illegal' (even if it's not expressly against the law)
Er, the problem is that this company did not write that algorithmic summation technology at all. They just licensed tech written by another company and made it into an app. Yahoo is not getting the tech.