The most noticeable trend among today's media companies is vertical integration, an attempt to control several related aspects of the media business at once, each part helping the other. Besides publishing magazines and books, Time Warner, for example, owns Home Box Office (HBO), Warner movie studios, various cable TV systems throughout the United States and CNN as well. The Japanese company Matsushita owns MCA Records and Universal Studios and manufactures broadcast production equipment. To describe the financial status of today's media is also to talk about acquisitions(并购). The media are buying and selling each other in unprecedented numbers and forming media groups to position themselves in the marketplace to maintain and increase their profits. In 1986, the first time a broadcast network had been sold, two networks were sold that year —ABC and NBC). Media acquisitions have skyrocketed(剧增)since 1980 for two reasons. The first is that most big corporations today are publicly traded companies, which means that their stock is traded on one of the nation's stock exchanges. This makes acquisitions relatively easy. A media company that wants to buy a publicly owned company can buy that company's stock when the stock becomes available. The open availability of stock in these companies means that anybody with enough money can invest in the American media industries, which is exactly how Rupert Murdoch joined the media business. The second reason for the increase in media alliances is that beginning in 1980, the Federal Communications Commission (FCC) gradually deregulated (解除管制) the broadcast media. Before 1980, for example, the FCC allowed one company to own only five TV stations, five AM radio stations, and five FM radio stations companies also were required to hold onto a station for three years before the station could be sold. The post-1980 FCC eliminated the three-year rule and raised the number of broadcast holdings allowed for one owner. This trend of media acquisitions is continuing throughout the 1990s, as changing technology expands the market for media products. The issue of media ownership is important. If only a few corporations direct the media industries in this country, the outlets for differing political viewpoints and innovative ideas could be limited. What do Time Warner and Matsushita have in common?