Abstract: Methods are provided for maintaining user privacy, and may include establishing a secret key for communication between a plurality of user devices, the plurality of user devices including a first user device associated with a requesting user and a second user device associated with a second user, wherein at least one server computer does not have access to the secret key; receiving from the first user device, a split-payment request message comprising encrypted data, the encrypted data included in the split-payment request message encrypted based on the secret key; generating an encrypted balance for the requesting user and the second user based on the encrypted data of the split-payment request message; and transmitting to the second user device, a split-payment confirmation message including the encrypted balance for the requesting user and/or the second user. Systems and computer program products are also provided.

Abstract: Methods are provided for maintaining user privacy, and may include establishing a secret key for communication between a plurality of user devices, the plurality of user devices including a first user device associated with a requesting user and a second user device associated with a second user, wherein at least one server computer does not have access to the secret key; receiving from the first user device, a split-payment request message comprising encrypted data, the encrypted data included in the split-payment request message encrypted based on the secret key; generating an encrypted balance for the requesting user and the second user based on the encrypted data of the split-payment request message; and transmitting to the second user device, a split-payment confirmation message including the encrypted balance for the requesting user and/or the second user. Systems and computer program products are also provided.

Abstract: Methods are provided for maintaining user privacy, and may include establishing a secret key for communication between a plurality of user devices, the plurality of user devices including a first user device associated with a requesting user and a second user device associated with a second user, wherein at least one server computer does not have access to the secret key; receiving from the first user device, a split-payment request message comprising encrypted data, the encrypted data included in the split-payment request message encrypted based on the secret key; generating an encrypted balance for the requesting user and the second user based on the encrypted data of the split-payment request message; and transmitting to the second user device, a split-payment confirmation message including the encrypted balance for the requesting user and/or the second user. Systems and computer program products are also provided.