This will almost certainly lead to a law suite by some large shareholder claiming the board of directors failed to perform their fiduciary duties (specifically their "duty of care" which basically says the board has to perform due diligence on all alternatives and choose the one that's best for the company). Since what's "best" is subjective, this is actually fairly typical and borderline inevitable with any large M&A transaction. There's very often some party that feels the board should have taken some alternate deal and by not doing so they've been materially damaged. If this goes to court, the board will demonstrate that their investment banking advisor (Qatalyst Partners if I recall correctly) demonstrated to them that they took the best deal on the table, and the other party will come up with arguments against it. Regardless of the outcome, and barring something crazy, the transaction will with MS will still go through regardless of this lawsuit's outcome.