I think you may have covered this, but I would first check whether there's some sort of contractual agreement between your current (consulting) company with the

I think you may have covered this, but I would first check whether there's some sort of contractual agreement between your current (consulting) company with the client, where no person would be poached (or recruited) within a certain period of time, during and after providing consulting services. This alone will save you a lot of grief. From the gist of your questions, I can certainly say that you're driven with the financial rewards. But do note that money is only part of the equation. There's a lot of stories abound similar to your situation where they've chosen the side of salary numbers and ended up being unhappy and downright unproductive. If you know your value, and the value for which employees at the client company pays, then you could certainly do the math. Asking a n% increase should be commensurate to the business value your bring to the table.