Grandfathered
As different from ‘Grandfather-Father-Son’, 'Grandfathered' is used in technology, infrastructure or policies to refer to an exemption from new rules or processes. Something which is allowed to violate a rule since it predates the existing rule which apply to all future cases.
Why it matters
The etymology stems from a legal clause from the Reconstruction Era used to disenfranchise Black Americans in new state constitutions to exclude them from voting in the late 19th century. New restrictive rules applied to voting registrations, but “grandfathered” existing registered voters so they were exempt. These “grandfathered” voters were white people only and allowed them to vote under different rule, whilst suppress black voting.
Instead try saying:
Further External Reading Link