In Invented by Law: Alexander Graham Bell and the Patent That Changed America, legal historian Christopher Beauchamp argues persuasively that historians must take patents and patent jurisprudence into consideration when analyzing business and technology development in the nineteenth century. Beauchamp uses Alexander Graham Bell's telephone patent as a lens through which to examine the evolution of patent law in the United States and Great Britain, and he illustrates how courts on opposite sides of the Atlantic arrived at markedly different conclusions regarding the validity of the patents that Bell filed in both nations. Such results not only influenced the development of corporate enterprises that dominated entire industries based on first-mover advantages acquired through patents, but also helped to reify the cultural notion of creative geniuses who set in motion technological paradigm shifts through their singular inventions. Beauchamp's study highlights the crucial role of patents in structuring networked industries, and deftly traces the interplay between courts and corporations in defining intellectual property and facilitating its monetization during the late nineteenth century.

Beauchamp's first chapter traces the development of patent laws and patenting in the United States during the first half of the nineteenth century. The lack of enforcement mechanisms within U.S. patent law forced inventors to turn to the courts in order to prosecute those who infringed on their intellectual property rights. An elite cadre of patent lawyers—some of whom had scientific training in addition to their knowledge of the law—began to emerge during this era, and this elite bar defined the scope of crucial patents in the mid- to late nineteenth century.

The second chapter traces the development of key telephone technologies, which took place alongside efforts to develop multiplex telegraph systems capable of transmitting multiple messages at the same time. Bell was backed by a fierce critic of monopolies (and his future father-in-law), Gardiner Greene Hubbard, who saw multiplex technology as a means to disrupt Western Union's stranglehold on the telegraph industry. Bell's inadvertent development, and subsequent patenting, of voice-transmission technology in 1876  set the stage for a conflict between Bell and his backers and Western Union, whose leaders refused to purchase the Bell patent and instead acquired rival patents developed by Elisha Gray and others. The two sides eventually settled in 1879, when Western Union, under pressure from financier Jay Gould, conceded the telephone market to Bell, but not before setting in motion infringement lawsuits that would eventually make their way to the U.S. Supreme Court.

The following chapters focus on the legal battles that eventually secured the validity of the Bell patents in the United States. The litigation revealed the influence of the elite patent bar and the willingness of a majority of Supreme Court justices to accept arguments by Bell's lawyers that his patent covered the broadest possible scope. At the same time, four of the court's justices were not comfortable with such a broad construction of Bell's patent rights, and Beauchamp highlights how the 1888 ruling could have swung in the other direction. An undercurrent of populist frustration over Bell's broadly construed patent, combined with opportunism on the part of businessmen who hoped to profit by forcing Bell to acquire their upstart telephone companies, led to pressure on the federal government to investigate the possibly fraudulent circumstances behind the issuance of the Bell patent. Two federal investigations failed to find a legal smoking gun, but they help to illustrate the highly politicized nature of patents and patent litigation in the United States during this era.

The focus of the narrative shifts to Europe in subsequent chapters. Beauchamp discusses differences in patent regimes among European nations in the late nineteenth century and how these differences affected efforts by Alexander Graham Bell, Thomas Edison, and other inventors to secure patents on key telephone components. Beauchamp explains how British courts reached markedly different conclusions than American courts regarding the scope and validity of Bell's patents. The British courts defined Bell's transmitter patents narrowly, while granting Edison's diaphragm patent broad scope. However, Bell's patent licensees in the United Kingdom were both better funded and better organized than Edison's local investors. They eventually acquired Edison's firm, thus forming the United Telephone Company. United Telephone used its control of key patents, its financial resources, and the court's largesse regarding the scope of its patents to eliminate competition and dominate the market until it was acquired by the British Post Office in 1912.

The final two chapters of Invented by Law discuss the key role of patents in providing American Bell with time to solidify its corporate structure and finances in the 1880s and early 1890s before the expiration of key patents in 1894. The firm developed business practices that emphasized Bell's proprietary control over key elements of telephone technology and embraced financial and technological integration with local operating companies. Path dependence from the earlier monopoly era helped to structure the terms of competition after 1894. Bell controlled lucrative markets in the Northeast and Mid-Atlantic and willingly surrendered unprofitable, rural regions of the Midwest, South, and West to the independents. It cross-subsidized affiliates in regions with intense competition and used its resources to offer a service that the independents could not—long distance. Bell, and later AT&T, used connection to its long lines as an incentive to implement technological standardization among local Bell and independent exchanges, giving the company effective control over the nation's telephone network.

Beauchamp's rich study of Bell's patents unpacks the significance of legal wrangling and court rulings on both sides of the Atlantic. For historians of business and technology, his book highlights the key role of political economy in shaping technology trajectories and business structures. Patents and patent litigation were essential elements in both of these fields, particularly with respect to the evolution of complex, networked industries in the early twentieth century. Invented by Law deftly details the political, economic, and social factors that shaped the legal interpretation of dry technical details on American and British patent applications.