Qui tacet consentire videtur

Meaning: He who is silent is taken to agree (limited application).
Explanation: Silence can sometimes be taken as consent in commercial and procedural contexts, but modern law requires active consent for most rights-sensitive transactions. Courts are careful with this maxim because silence is often ambiguous.
Example: A student’s failure to respond to an optional waiver email should not generally be treated as consent to give up data privacy — explicit consent is preferred.