What is “silent consent drift”?

Silent consent drift describes the gradual degradation of meaningful consent over time:

How it happens: Subscriber opted in years ago. Circumstances, preferences, or interests have changed. They forgot they subscribed. They do not recognize your brand anymore. Technical consent exists but meaningful consent has eroded.

Warning signs: Long-dormant subscribers suddenly complaining. "I never signed up for this" from old list members. Low engagement from aging segments. Spam trap activity in older addresses.

Risks: Complaints from recipients who technically consented. Reputation damage from perceived spam. Legal ambiguity about consent validity.

Prevention: Regular re-engagement campaigns for dormant subscribers. Preference refresh requests periodically. Suppression of persistently inactive contacts. List hygiene practices maintaining active consent.

Consent is not permanent. Old opt-ins without recent engagement represent drifted consent.