The United States Patent and Trademark Office has granted thousands of patents for inventions whose purpose is to facilitate the sexual pleasure of their users. These "pleasure patents" raise a range of novel questions about both patent theory and the relationship between law and sexuality more broadly. Given that "immoral" inventions were long excluded from the patent system, and that sexual devices were widely criminalized for much of the past 150 years, how have patentees successfully framed the contributions of their sexual inventions? If a patentable invention must be both new and useful, how have patentees described the utility of sexual pleasure? This Article identifies several hundred patents that the USPTO has formally classified as improving sexual stimulation and intercourse, and it closely examines how patentees have described the utility of sexual pleasure over time. In describing the utility of technologies such as phalluses, vibrators, and virtual reality systems, patentees employ a diverse and rich set of themes about the purposes and social values of sexual pleasure. By facilitating sexual pleasure, these patented technologies can, according to their inventors: improve marital harmony, overcome female frigidity, calm fears of HIV transmission, reduce sexual assault, suppress demand for sex work, minimize the loneliness of single people, facilitate LGBTQIA relationships, and promote the emotional well-being of people with disabilities. As social and sexual norms have changed over time, so too have the various explanations for the social value of pleasure patents. This Article shows that the patent system is an underappreciated, and perhaps unexpected, archive of historical and contemporary sexual norms.