This document proposes using the HMAC algorithm to enable secure data deduplication on cloud servers. It first provides background on data deduplication and the need for integrity auditing and secure deduplication when storing data in the cloud. It then describes the HMAC algorithm and how it works to generate authentication tags for data using cryptographic hash functions and secret keys. The security of HMAC is analyzed and it is shown to be as secure as attacks on the underlying hash function. Finally, the document concludes that using HMAC allows for secure data deduplication by enabling the verification of data ownership through proof of ownership protocols while maintaining data integrity and confidentiality.