Counterfeit integrated circuits (ICs) have become a significant security concern in the semiconductor industry as a result of the increasingly complex and distributed nature of the supply chain. These counterfeit chips may result in performance degradation, profit reduction, and reputation risk for the manufacturer. Therefore, developing effective countermeasures against such malpractices is becoming severely crucial. As a part of our research effort we develop lightweight authentication techniques using Physically Unclonable Functions (PUFs) and watermarks for detecting counterfeit ICs.