grandfather (someone or something)

To exempt certain people or things from new limitations or restrictions, thus allowing them to continue doing or benefiting from something as they did before. This can be done through the use of a "grandfather clause." If they change the pension plan, they better grandfather us! Helmets become mandatory in the NHL in 1979, but the league grandfathered players already active at that point. Only new hires have to live in the city to work here. The rest of us were grandfathered when they drew up the new contract.