When you are making decisions on behalf of a corporation, you legally have to make the best decision for the shareholders. There's a lot of wiggle-room in that,

When you are making decisions on behalf of a corporation, you legally have to make the best decision for the shareholders. There's a lot of wiggle-room in that, but the courts will see through the most egregious stuff. So if you own non-voting shares and the voting shares decide not to give dividends and instead buy a useless corporate yacht for themselves to use, you can sue.