After the prior discussion of the fundamentals of patents and a method of drafting patents in Chapter 1, principles of drafting excellent patents in Chapter 2, and the most common patent mistakes in Chapter 3, Chapter 4 presents several examples of patents that illustrate the concept of “litigation-proof patents”.  To be exact, five patents are discussed.

However, these five patents are not all high-quality patents. Some of the patents are excellent, but others are not.  These particular patents have been selected to conclude the book because all of these patents are inherently interesting in their subject matters, and because they illustrate both the concept of “litigation-proof patents” and how patents lose their value when they commit the most common mistakes in patent drafting.

The book concludes with Table 4-5, comparing the patents discussed in Chapter 4 against the most common patent mistakes.