unknown to somebody
unknown to (one)
With someone being unaware (of something). Unknown to Jacobson, the other two partners had drawn up the deal in such a way that they would have full control of the company in two years' time. My wife invited her entire family to come stay with us for Christmas—unknown to me.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
unknown to somebodywithout the person mentioned being aware of it: Unknown to me, he had already signed the agreement.
Farlex Partner Idioms Dictionary © Farlex 2017