I’m starting to learn about Macrovision, which is a company that produces every kind of encryption and copy protection hardware/software for any imaginable type of medium. However, I’m interested in the product Macrovision–the copy protection introduced into the home video market in 1985 with the release of “The Cotton Club” video cassette. Macrovision relies on the corruption of the Automatic Gain Control signal to prohibit recording from one cassette to another.
In 1985, Macrovision applied for and received the patent “Method and Apparatus for Processing a Video Signal as to Prohibit the Making of Acceptable Video Tape Recordings Thereof.” It’s interesting to read through the patent because the language is so dispassionate about the invention that it describes. Patent applications don’t need justifications of why this object should exist or what it can be used for. Even the concept of what it means to make an “acceptable” video tape recording remains unexplored. Furthermore, the specific applicants for the patent go virtually unreferenced throughout the body of the text. The inventor’s motivations are as irrelevant as the potential consequences of the product. No one is asking whether you intend to use your product for good or for evil. Not that they should be. Still, it’s important to acknowledge that couching the technology within such descriptive and seemingly neutral language allows all of these inventions to appear equal before the law, when in fact they exist within a larger system of economic competition, monopolies, and control.
Yes, no patent is an island, and at the very least, patent applications are required to reference other patents in their quest for legitimacy. Macrovision’s 1985 Patent is referenced in Patent Number 4,695,901, filed one year later in March 1986 by Macrovision. This document, “Method and Apparatus for Removing Pseudo-sync and/or AGC Pulses from a Video Signal,” patents the means of undoing the gain signal corruption that Macrovision introduced in 1985. As far as I know, Macrovision didn’t intend to use this technology in any of their products. They just didn’t want anyone else to. In this case, patents, which were written into U.S. law to spur innovation, create stasis, as Macrovision became the unchallenged authority on video signal manipulation in video cassette recorders.
