Ex parte communications are prohibited in patent interferences to maintain the fairness and integrity of the proceedings. The MPEP 2307.01 explains: "Since an interference involves two or more parties, the integrity of the process requires the opportunity for the opposing party to participate in communications or actions regarding any involved application or patent." This prohibition ensures that all parties have equal access to information and prevents any unfair advantage. It also maintains transparency in the process and upholds the adversarial nature of interference proceedings, where both parties should have the opportunity to respond to all communications and actions related to the case. To learn more: ex parte communications patent interference procedural fairness USPTO rules PTAB proceedings