As a hardware designer or a company, you want to protect your design intellectual property (IP) from being misused (by users, competitors, silicon foundry, etc). We will cover how you can build such protection during the design process which can be used as an evidence to support law enforcement protection. You are expected to understand the basic digital logic design knowledge covered in week 1. We will use several NP-hard problems as examples to illustrate the concepts of IP protection. These problems (graph vertex coloring problem and graph partitioning problem) will be introduced in the lecture and you do not need to know the concept of NP-complete.