MADISON RIVER: In 2005, North Carolina ISP Madison River Communications blocked the voice-over-internet protocol (VOIP) service Vonage. Vonage filed a complaint with the FCC after receiving a slew of customer complaints. The FCC stepped in to sanction Madison River and prevent further blocking, but it lacks the authority to stop this kind of abuse today.

COMCAST: In 2005, the nation’s largest ISP, Comcast, began secretly blocking peer-to-peer technologies that its customers were using over its network. Users of services like BitTorrent and Gnutella were unable to connect to these services. 2007 investigations from the Associated Press, the Electronic Frontier Foundation and others confirmed that Comcast was indeed blocking or slowing file-sharing applications without disclosing this fact to its customers.

TELUS: In 2005, Canada's second-largest telecommunications company, Telus, began blocking access to a server that hosted a website supporting a labor strike against the company. Researchers at Harvard and the University of Toronto found that this action resulted in Telus blocking an additional 766 unrelated sites.

AT&T: From 2007–2009, AT&T forced Apple to block Skype and other competing VOIP phone services on the iPhone. The wireless provider wanted to prevent iPhone users from using any application that would allow them to make calls on such "over-the-top" voice services. The Google Voice app received similar treatment from carriers like AT&T when it came on the scene in 2009.

WINDSTREAM: In 2010, Windstream Communications, a DSL provider with more than 1 million customers at the time, copped to hijacking user-search queries made using the Google toolbar within Firefox. Users who believed they had set the browser to the search engine of their choice were redirected to Windstream's own search portal and results.

MetroPCS: In 2011, MetroPCS, at the time one of the top-five U.S. wireless carriers, announced plans to block streaming video over its 4G network from all sources except YouTube. MetroPCS then threw its weight behind Verizon's court challenge against the FCC's 2010 open internet ruling, hoping that rejection of the agency's authority would allow the company to continue its anti-consumer practices.

PAXFIRE: In 2011, the Electronic Frontier Foundation found that several small ISPs were redirecting search queries via the vendor Paxfire. The ISPs identified in the initial Electronic Frontier Foundation report included Cavalier, Cogent, Frontier, Fuse, DirecPC, RCN and Wide Open West. Paxfire would intercept a person's search request at Bing and Yahoo and redirect it to another page. By skipping over the search service's results, the participating ISPs would collect referral fees for delivering users to select websites.

AT&T, SPRINT and VERIZON: From 2011–2013, AT&T, Sprint and Verizon blocked Google Wallet, a mobile-payment system that competed with a similar service called Isis, which all three companies had a stake in developing.

EUROPE: A 2012 report from the Body of European Regulators for Electronic Communications found that violations of Net Neutrality affected at least one in five users in Europe. The report found that blocked or slowed connections to services like VOIP, peer-to-peer technologies, gaming applications and email were commonplace.

VERIZON: In 2012, the FCC caught Verizon Wireless blocking people from using tethering applications on their phones. Verizon had asked Google to remove 11 free tethering applications from the Android marketplace. These applications allowed users to circumvent Verizon's $20 tethering fee and turn their smartphones into Wi-Fi hot spots. By blocking those applications, Verizon violated a Net Neutrality pledge it made to the FCC as a condition of the 2008 airwaves auction.

AT&T: In 2012, AT&T announced that it would disable the FaceTime video-calling app on its customers' iPhones unless they subscribed to a more expensive text-and-voice plan. AT&T had one goal in mind: separating customers from more of their money by blocking alternatives to AT&T’s own products.

VERIZON: During oral arguments in Verizon v. FCC in 2013, judges asked whether the phone giant would favor some preferred services, content or sites over others if the court overruled the agency's existing open internet rules. Verizon counsel Helgi Walker had this to say: "I'm authorized to state from my client today that but for these rules we would be exploring those types of arrangements." Walker's admission might have gone unnoticed had she not repeated it on at least five separate occasions during arguments.