to the descriptions provided in their patents, which are bundled into portfolios for licensing. Myhrvold has described his goal for Intellectual Ventures as helping to create a market for patent-backed securities. The company's business practices have caused controversy, however, with some deprecating the firm as a patent troll. Myhrvold has publicly defended his firm's practices, arguing that they foster innovation by serving as a marketplace for intellectual property. He has noted that many of the largest companies in Silicon Valley, including Google, Apple, and Facebook, have also bought large patent portfolios and used litigation to protect them, but he has criticized them as focusing too much on creating "tools or toys for rich people." In the popular press, Myhrvold's company Intellectual Ventures has been repeatedly accused of acting as patent trolls and stifling innovation by buying patents and then forcing inventors to license their ideas by means of litigation. Walt Mossberg interviewed Myhrvold about Intellectual Ventures' role as a "patent troll" during the 10th annual All Things Digital conference. This American Life's Laura Sydell ran an investigative story about patent trolling and Intellectual Ventures' role in that business. According to The New York Times, Intellectual Ventures at one point controlled nearly 70,000 intellectual property assets (patents and patents pending) that it has used to generate approximately $3 billion in revenues, primarily in the form of license fees from large corporations. The company responds that it has returned more than $500 million to individual inventors and most of the remaining revenues to its investors. Nuclear power Myhrvold is vice chairman of TerraPower, a spin-out of Intellectual Ventures that is developing a new kind of nuclear reactor, known as a traveling-wave reactor, that is designed to be safer, cheaper, and cleaner than current nuclear power plants. In 2020, the company launched a joint venture with GE Hitachi Nuclear Energy to build and operate a prototype reactor of this kind that combines a molten-sodium reactor with a molten salt energy storage system. Science In addition to his business activities, Myhrvold is a working scientist who has published original, peer-reviewed research in the fields of paleobiology, climate science, and astronomy. A prize-winning nature and wildlife photographer, he has also been involved with paleontological research on expeditions with the Museum of the Rockies. His work has appeared in scientific journals including Science, Nature, Paleobiology, PLOS One, and the Physical Review, as well as in Fortune,