The proliferation of cloud services has significantly alleviated the data management, maintenance, and archival burdens for data owners by providing scalable storage solutions. However, data owners cannot guarantee the integrity and immutability of their data after uploading their data to the cloud server and deleting local copies. Public cloud data auditing protocols address this issue effectively by allowing data owners to verify that their data remains unchanged over time. While most protocols prioritize audit efficiency and reducing communication overhead, they often overlook the problem of redundant data storage. Specifically, when multiple users upload the same data repeatedly, the cloud server must store multiple tags for the same data, leading to unnecessary consumption of storage resources. To bridge this gap, this paper introduces an innovative public auditing framework that comes up with the concept of aggregated tags, which allows the cloud server to maintain a set of aggregated tags for each file. Notably, the size of the aggregated tag remains the same as that of a single tag, thereby conserving cloud-side storage space. Moreover, only an aggregated public key, rather than all users’ public keys, is needed for the file in the verification processes. Our framework also ensures that there is only one round of interaction between cloud servers and auditors without the involvement of data owners, which maintains the same efficiency level as previous public auditing protocols.