Information causality is a physical principle suggested in 2009.
[1] Information causality states that the information gain a receiver (Bob) can reach about data, previously unknown to him, from a sender (Alice), by using all his local resources and
bits; and that this limitation should hold even in the case where Alice and Bob pre-share a physical non-signaling resource, such as an entangled quantum state.
The principle assumes classical communication: if quantum bits were allowed to be transmitted, the information gain could be higher (for example if Alice and Bob pre-share some entangled qubits) as demonstrated in the quantum superdense coding protocol.
[2] The principle is respected by all correlations accessible with quantum physics, while it excludes all correlations which violate the quantum Tsirelson bound for the CHSH inequality.