From: Rabbi Akiva Eiger
To: Rabbi Zalman
A man told a woman to take an object as a deposit, then declared kiddushin while both held it; she was silent and later threw it back. Rabbi Akiva Eiger disagrees with the correspondent's firm ruling that silence here constitutes consent under sha'as matan ma'os, and constructs a multi-layered lenient analysis based on the pikadon framing, a sfek sfeika, and the woman's own testimony. He concludes the kiddushin are not valid, conditional on the correspondent's agreement.
Source: Shu"t Rabbi Akiva Eiger §97