California law requires that holders of a majority of each class of stock approve a sale of a company. For founders that hold the majority of common stock in their company, this may seem like protection, but it's not, due to a loophole. In the first place, Delaware simply requires holders of a majority of stock, not of each class. California law and Delaware law disagree as to which of the two laws apply to Delaware corporations doing business in California, although California law has clearly stated the requirements for a business to qualify as a California corporation. More importantly, a sales of a company's assets does not require stockholder approval; it can be approved simply by a majority of the Board of Directors, and is for most intents and purposes equivalent to a sale of the company.

This causes abuse of minority stockholders, and could use a legislative solution, but until then, beware.

Also, check the requirements to change the bylaws of the company, as I have seen these secretly changed to reduce quorum requirements.

Disclaimer: This is not legal advice.