The Stop Online Piracy Act (SOPA) was a controversial United States bill introduced by U.S. Representative Lamar S. Smith (R-TX) to expand the ability of U.S. law enforcement to combat online copyright infringement and online trafficking in counterfeit goods. Provisions included the requesting of court orders to bar advertising networks and payment facilities from conducting business with infringing websites, and web search engines from linking to the websites, and court orders requiring Internet service providers to block access to the websites. The proposed law would have expanded existing criminal laws to include unauthorized streaming of copyrighted content, imposing a maximum penalty of five years in prison.
Proponents of the legislation said it would protect the intellectual-property market and corresponding industry, jobs and revenue, and was necessary to bolster enforcement of copyright laws, especially against foreign-owned and operated websites. Claiming flaws in present laws that do not cover foreign-owned and operated websites, and citing examples of active promotion of rogue websites by U.S. search engines, proponents asserted that stronger enforcement tools were needed. The bill received strong, bipartisan support in the House of Representatives and the Senate. It also received support from the following organizations: Fraternal Order of Police, the National Governors Association, The National Conference of Legislatures, the U.S. Conference of Mayors, The National Association of Attorneys General, the Chamber of Commerce, the Better Business Bureau, the AFL–CIO and 22 trade unions, the National Consumers League, and over a hundred associations representing industries throughout the economy which claim that they are being harmed by online piracy.
Opponents claimed that the proposed legislation threatened free speech and innovation, and enabled law enforcement to block access to entire Internet domains due to infringing content posted on a single blog or webpage. They also claimed that SOPA would bypass the "safe harbor" protections from liability presently afforded to websites by the Digital Millennium Copyright Act. Some library associations also claimed that the legislation's emphasis on stronger copyright enforcement would expose libraries to prosecution. Other opponents claimed that requiring search engines to delete domain names violated the First Amendment and could begin a worldwide arms race of unprecedented Internet censorship.
On January 18, 2012, the English Wikipedia, Google, and an estimated 7,000 other smaller websites coordinated a service blackout, in protest against the bill. Wikipedia said more than 162 million people viewed its banner. Other protests against SOPA and PIPA included petition drives, with Google stating it collected over seven million signatures, boycotts of companies and organizations that support the legislation, and an opposition rally held in New York City.
In response to the protest actions, the Recording Industry Association of America (RIAA) stated, "It's a dangerous and troubling development when the platforms that serve as gateways to information intentionally skew the facts to incite their users and arm them with misinformation", and "it's very difficult to counter the misinformation when the disseminators also own the platform."
Access to websites of several pro-SOPA organizations and companies such as RIAA, CBS.com, and others was impeded or blocked with denial-of-service attacks which started on January 19, 2012. Self-proclaimed members of the "hacktivist" group Anonymous claimed responsibility and stated the attacks were a protest of both SOPA and the United States Department of Justice's shutdown of Megaupload on that same day.
Some opponents of the bill support the Online Protection and Enforcement of Digital Trade Act (OPEN) as an alternative. On January 20, 2012, House Judiciary Committee Chairman Smith postponed plans to draft the bill: "The committee remains committed to finding a solution to the problem of online piracy that protects American intellectual property and innovation ... The House Judiciary Committee will postpone consideration of the legislation until there is wider agreement on a solution."
This summary is from Wikipedia.