If you are a member of a union and there is a strong successorship clause in the union contract, then you would probably have been "grandfathered" in, depending on the deal the union made. Being "grandfathered" is usually only used in union contracts. When a company comes in and buys out another, employees are "fair game," unless there is a union contract in place. If there is a union contract with a strong successorship clause, then it is mandatory for the buying company to negotiate with the union and that is when "grandfathering" is brought to the table.