One totally transparent method is for the acquirer to pay relatively little for the company, and provide most of the benefit as compensation or retention bonuses. Directors of the selling firm have a fiduciary duty to do what’s best for all shareholders (and can’t legally accept a deal that benefits them at the expense of minority shareholders), but if the seller doesn’t have a viable business and only receives 1 acquihire offer, there’s no reason to expect it to be strong, particularly if the seller is out of cash.
That’s not a lawyer-y way around the cap table, it’s that the company’s value is minimal.
Another possibility is that they’ve taken outside capital and those shareholders purchased “preferred” shares with a liquidation preference. If that’s the case, they’d get their investment principal back before common shareholders (which includes holders of exercised options) received anything. If the company is out of cash and accepts an offer for less than was raised, common shares may be worthless.
If this sounds like a tough situation that can easily lead to conflicts of interest, that’s about right.
Acceleration is a meaningful clause to receive and may even end up making a difference, but it won’t make the shares more valuable than the business actually is and it won’t get around the buyer’s intent.