Legal Question in Employment Law in California

I'm not sure what you mean when you say the new company wiped out all your previous years' work. It is not unusual, in fact quite common, that when a company is purchased by another, employees acquired with the business become new employees of that company. There are exceptions, but that depends any contracts entered into between the companies or with the employees.

This does not necessarily mean that any vested benefits you might have earned are lost. But whether the purchasing company also acquired the obligations of the old company, again, depends on the contract they made. If the new employer claims they do not owe any vested vacation pay or other benefits, you may have to go after the old company for compensation. Some employees sue both companies and let them fight it out over who owes the benefits.

It starts with asking questions and trying to get as much information as possible. If necessary, you may have to hire an attorney to assist you with this.