When implementing a new management system based on ISO standards, experts usually invoke the grandfather clause as a way to relieve the enforcement of some requirements. When, where, and how often can the grandfather clause be invoked?

The grandfather clause is a statement that an organization makes to declare that, before a specific date, certain individuals or processes do not comply with company rules or regulations.

The grandfather clause has three basic components: [Individual/process] + [area of grandfathering] + [date].

Here is an example of a grandfather clause taken from a quality manual:
The effective implementation date of the quality management system is Sept. 1, 2012. This date is also used for grandfathering* of suppliers, employees, and records.
* The grandfather clause is used as a way to grant exemptions to all those who were part of the organization before the new quality management system rules went into effect.

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