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The 4chan homepage on August 23, 2010
|Type of site||Imageboard|
|Launched||October 1, 2003|
|Alexa rank||1,032 (April 2014[update])|
The 4chan homepage on August 23, 2010
|Type of site||Imageboard|
|Launched||October 1, 2003|
|Alexa rank||1,032 (April 2014[update])|
4chan is an English-language imageboard website. Users generally post anonymously, with the most recent posts appearing above the rest. 4chan is split into various boards with their own specific content and guidelines. Registration is not required, nor is it possible (except for staff).
Launched on October 1, 2003, its boards were originally used for the posting of pictures and discussion of manga and anime, as the site was modelled on Japanese imageboards. The site quickly became popular and expanded, though much of 4chan's content still features otaku, anime and other Japanese cultural influences.
The site has been linked to Internet subcultures and activism, most notably Project Chanology. 4chan users have been responsible for the formation or popularization of Internet memes such as lolcats, Rickrolling, "Chocolate Rain", Pedobear and many others. The site's "Random" board, also known as "/b/", was the site's first forum, and is the one that receives the most traffic. As its name suggests, the Random board has minimal rules on posted content. Gawker once jokingly claimed that "reading /b/ will melt your brain". The site's anonymous community and culture have often provoked media attention. For media planners, this enterprise is "further proof that creativity is everywhere and new media is less accessible" to advertisement agencies.
4chan has been instrumental in hijacking Internet destinations for pranks, so that, for example, images of Rick Astley appeared instead of the page that was searched for; the coordination of attacks against other websites and Internet users; and reactions to threats of violence that have been posted on the site. The Guardian once summarized the 4chan community as "lunatic, juvenile... brilliant, ridiculous and alarming."
4chan was started in 2003 in the bedroom of a then-15-year-old student from New York City named Christopher Poole, who posts as "moot". Prior to starting 4chan, Poole had been a regular participant on the Something Awful forums. He intended 4chan to be a place to discuss Japanese comics and anime, an American counterpart to the popular Japanese Futaba Channel ("2chan") imageboard. Poole originally used the Futaba Channel to obtain anime-related images, and liked the concept of a message board where people anonymously shared images, which eventually led to his idea of creating a similar English-based website. During the creation of 4chan, he obtained the source code for the Futaba Channel website, and translated the Japanese text into English using Altavista's Babelfish online translator. When he first created the website, it had only two boards: "/a/ – Anime/General" and "/b/ – Anime/Random"; over time more boards were created, and /b/ was eventually renamed to simply "/b/ – Random".
The activity of 4chan takes place on message boards and imageboards. The website is split into six categories: Japanese culture, Interests, Creative, Adult (18+), Other, and Misc (18+). These provide for on-topic boards to discuss anime, manga, technology, sport, photography, music, hentai, torrents, travel, physical fitness, as well as a random board. 4chan originally hosted discussion boards on a separate domain called "world4ch", but these were later moved to the dis.4chan.org subdomain. The site has had at least one employee, a programmer whom Poole met via online Tetris. All other moderators are volunteers. The boards that attract the largest amount of traffic, from greatest to least, are /b/ (Random), /v/ (Video games), /a/ (Anime and Manga), and /s/ (board intended for sharing explicit images).
During the early days of 4chan, the boards that originally existed were the anime, random, cute, hentai, and yaoi boards; a lolicon board also existed at /l/, but after being disabled for a week around the turn of the year 2004 it was removed in October 2004. The /g/ board also was initially dedicated to guro, before it was deleted and later remade as the "technology" board. During 2004, 4chan briefly went offline, then returned fully online a few months later. Following 4chan's return, non-anime related boards, such as the weapons, automobile, and video games boards, were introduced. In 2008, the "Japan/General" board at /jp/ was created for topics that did not fit under the anime and manga category of /a/; /jp/ was later renamed to "Otaku Culture".
4chan is one of the Internet's most trafficked imageboards, according to the Los Angeles Times. 4chan's Alexa rank is generally around 700, though it has been as high as number 56 at times. It is provided to its users free of charge and consumes a large amount of bandwidth; as a result, its financing has often been problematic. Poole acknowledges that donations alone cannot keep the site online, so he has turned to advertising to help make ends meet. However, the explicit content hosted on 4chan has deterred businesses who do not want to be associated with the site's content. In January 2009, Poole signed a new deal with an advertising company; in February 2009, he was $20,000 in debt and the site was continuing to lose money. The 4chan servers were moved from Texas to California in August 2008, which upgraded the maximum bandwidth throughput of 4chan from 100Mbit/s to 1Gbit/s.
Unlike most web forums, 4chan does not have a registration system, allowing users to post anonymously. Any nickname may be used when posting, even one that has been previously adopted, such as "Anonymous" or "moot". In place of registration, 4chan has provided tripcodes as an optional form of authenticating a poster's identity. As making a post without filling in the "Name" field causes posts to be attributed to "Anonymous", general understanding on 4chan holds that Anonymous is not a single person but a collective (hive) of users. Moderators generally post without a name even when performing sysop actions. A "capcode" may be used to attribute the post to "Anonymous ## Mod", although moderators often post without the capcode. In a 2011 interview on Nico Nico Douga, Poole explained that there are approximately 20 volunteer moderators active on 4chan. 4chan also has a junior moderation team, called "janitors", who may delete posts or images and suggest that the normal moderation team ban a user, but who can not post with a capcode. Revealing oneself as a janitor is grounds for immediate dismissal.
In January 2011, Poole announced the deletion of the /r9k/ ("ROBOT9000") and /new/ (News) boards, saying that /new/ had become devoted to racist discussions, and /r9k/ no longer served its original purpose of being a test implementation of xkcd's ROBOT9000 script. During the same year, the /soc/ board was created in an effort to reduce the number of socialization threads on /b/. /r9k/ was restored on October 23, 2011, along with /hc/ ("Hardcore", previously deleted), /pol/ (a rebranding of /new/) and the new /diy/ board, in addition to an apology by Poole where he recalls how he criticized the deletion of Encyclopedia Dramatica, and realized that he had done the same.
4chan has been the target of occasional denial of service attacks. For instance, on December 28, 2010, 4chan went down due to a such an attack. Christopher Poole said on his blog "We now join the ranks of MasterCard, Visa, PayPal, et al.—an exclusive club!"
As of September 28, 2012, 4chan introduced a "4chan pass", which when purchased "allows users to bypass typing a reCAPTCHA verification when posting and reporting posts on the 4chan image boards". The money raised from the passes will go towards supporting the site.
On October 1, 2013, 4chan became 10 years old.
Christopher Poole kept his real life identity hidden until it was revealed on July 9, 2008, in The Wall Street Journal. Before that time he had used the alias "moot". The same day, Lev Grossman of Time published an interview describing Poole's influence as a non-visible administrator as "one of the most [significant]" on the evolution of content collaboration. Although Grossman's article began with the confession that "I don't even know his real name", he claimed to identify moot as Christopher Poole. Later, on July 10, Grossman admitted that there was an outside chance that Christopher Poole was not moot's real name, rather an obscure reference to a 4chan inside joke. The Washington Post concurred that "Christopher Poole" could be "all a big hoax, a 'gotcha'. It would be just what you'd expect from the creator of 4chan." In March 2009, Time backpedaled somewhat on the issue by placing the moot persona on the 2009 Time 100 finalists list.
Prior to the Wall Street Journal and Time interviews, Poole deliberately kept his real identity separate from 4chan. He told Grossman "my personal private life is very separate from my Internet life ... There's a firewall in between." As moot, he has spoken at conferences at Yale University and Massachusetts Institute of Technology. A 2008 article in The Observer had him down as "the most influential web entrepreneur you've never heard of", though he has since been described in more limited terms such as "benefactor".
In February 2009, The Washington Post reported that Poole had attended Virginia Commonwealth University for a few semesters before dropping out. It reported that Christopher Poole was living with his mother while looking for a way to make money from owning 4chan.
In April 2009, Poole was voted the world's most influential person of 2008 by an open Internet poll conducted by Time magazine. The results were questioned even before the poll completed, as automated voting programs and manual ballot stuffing were used to influence the vote. 4chan's interference with the vote seemed increasingly likely, when it was found that reading the first letter of the first 21 candidates in the poll spelled out a phrase containing two 4chan memes: "mARBLECAKE. ALSO, THE GAME."
On September 12, 2009, Poole gave a talk on why 4chan has a reputation as a "Meme Factory" at the Paraflows Symposium in Vienna, Austria, which was part of the Paraflows 09 festival, themed Urban Hacking. In this talk, Poole mainly attributed this to the anonymous system, and to the lack of data retention on the site ("The site has no memory.").
On February 10, 2010, Poole spoke at the TED2010 conference in Long Beach, California. He spoke about the increasing prevalence of persistent user identities and the sharing of personal information on sites like Facebook and Twitter and he also spoke about the value of anonymous posting on sites like 4chan. Fred Leal of the Brazilian newspaper Estadão said his inclusion in the conference "indicates that something extraordinary is happening... [4chan] challenges every Internet convention: it is, alone, the antithesis of Google, social networking sites, and blogs."
In 2010, Poole was reported to have raised $625,000 to create a new online enterprise, called "Canvas". The website opened on January 31, 2011, and features digitally modified images uploaded by users who are required to self-identify using Facebook Connect. However, Facebook Connect is no longer required and users can post anonymously.
In April 2010, Poole gave evidence in the trial United States of America v. David Kernell as a government witness. As a witness, he explained the terminology used on 4chan to the prosecutor, ranging from "OP" to "lurker". He also explained to the court the nature of the data given to the FBI as part of the search warrant, including how users can be uniquely identified from site audit logs.
In a 2010 interview, Poole discussed his belief in the value of multiple identities, including anonymity, in contrast to the merge of online and real-world identities occurring on Facebook and many other social networking sites.
4chan has been labeled as the starting point of the Anonymous meme by The Baltimore City Paper, due to the norm of posts signed with the "Anonymous" moniker. The National Post's David George-Cosh said it has been "widely reported" that Anonymous is associated with 4chan and 711chan, as well as numerous Internet Relay Chat (IRC) channels.
Through its association with Anonymous, 4chan has become associated with Project Chanology, a worldwide protest against the Church of Scientology held by members of Anonymous. On January 15, 2008, a 4chan user posted to /b/, suggesting participants "do something big" against the Church of Scientology's website. This message resulted in the Church receiving threatening phone calls. It quickly grew into a large real-world protest. Unlike previous Anonymous attacks, this action was characterized by 4chan memes including rickrolls and Guy Fawkes masks. The raid drew criticism from some 4chan users who felt it would bring the site undesirable attention.
The "random" board, /b/, follows the design of Futaba Channel's Nijiura board. It was the first board created, and is by far 4chan's most popular board, with 30% of site traffic. Gawker.com's Nick Douglas summarized /b/ as a board where "people try to shock, entertain, and coax free porn from each other." /b/ has a "no rules" policy, except for bans on certain illegal content, such as child pornography, invasions of other websites (posting floods of disruptive content), and under-18 viewing, all of which are inherited from site-wide rules. The "no invasions" rule was added in late 2006, after /b/ users spent most of the summer "invading" Habbo Hotel. The "no rules" policy also applies to actions of administrators and moderators, which means that users may be banned at any time, for any reason, including no reason at all. Due partially to its anonymous nature, board moderation is not always successful—indeed, the site's anti-child pornography rule is a subject of jokes on /b/. Christopher Poole told The New York Times, in a discussion on the moderation of /b/, that "the power lies in the community to dictate its own standards" and that site staff simply provided a framework.
The humor of /b/'s many users, who refer to themselves as "/b/tards", is often incomprehensible to newcomers and outsiders, and is characterized by intricate inside jokes and dark comedy. Users often refer to each other, and much of the outside world, as fags. They are often referred to by outsiders as trolls, who regularly act with the intention of "doing it for the lulz": a corruption of "LOL" used to denote amusement at another's expense. The New York Observer has described posters as "immature pranksters whose bad behavior is encouraged by the site's total anonymity and the absence of an archive". Douglas said of the board, "reading /b/ will melt your brain", and cited Encyclopedia Dramatica's definition of /b/ as "the asshole of the Internets". Mattathias Schwartz of The New York Times likened /b/ to "a high-school bathroom stall, or an obscene telephone party line", while Baltimore City Paper wrote that "in the high school of the Internet, /b/ is the kid with a collection of butterfly knives and a locker full of porn." Wired describes /b/ as "notorious".
Each post is assigned a post number. Certain post numbers are sought after with a large amount of posting taking place to "GET" them. A "GET" occurs when a post's number ends in a special number, such as 12345678, 22222222, or every millionth post. A sign of 4chan's scaling, according to Poole, was when GETs lost meaning due to the high post rate resulting in a GET occurring every few weeks. He estimated /b/'s post rate in July 2008 to be 150,000–200,000 posts per day.
Internet memes are catchphrases or images that spread quickly, peer to peer, across the Internet. Many Internet memes have originated on 4chan, usually /b/, as its fast moving, crowd psychology nature enables content to quickly be passed on to large numbers of viewers. Other memes originating on the site have gained media attention of a lesser degree. These include "So I herd u liek mudkipz" [sic], which involves a phrase based on Pokémon and which generated numerous YouTube tribute videos, and the term "an hero" [sic] as a synonym for suicide, after a misspelling in the MySpace online memorial of seventh grader Mitchell Henderson. 4chan, and other websites, such as the satirical Encyclopedia Dramatica, have also contributed to the development of significant amounts of leetspeak. Adult fans of My Little Pony: Friendship Is Magic are also known to frequent 4chan, having had a board dedicated to their interest.
A lolcat is an image combining a photograph of a cat with text intended to contribute humour. The text is often idiosyncratic and grammatically incorrect. In 2005, the meme was widely popularized by 4chan in the form of "Caturday". Every Saturday, users posted pictures of cats with image macros relating to that day's theme.
In 2005, a meme known as the "duckroll" began, after Poole used a word filter to change "egg" to "duck" across 4chan. Thus, words such as "eggroll" were changed to "duckroll". This led to a bait-and-switch in which external links disguised as relevant to a discussion instead led to a picture of a duck on wheels.
In March 2007, the trailer for the video game Grand Theft Auto IV was released. Its immense popularity caused publisher Rockstar Games' website to crash. An unidentified 4chan user applied the concept of the duckroll to what appeared to be a link to the trailer on YouTube, but instead showed the music video for Rick Astley's 1987 song "Never Gonna Give You Up". Thus, the "rickroll" was born. In an interview with the Los Angeles Times, Astley said he found the meme "bizarre and funny".
A link to the YouTube video of Tay Zonday's song "Chocolate Rain" was posted on /b/ on July 11, 2007. The Age reported that 4chan posters urged each other to "swarm" the video on YouTube and thus increase its ranking. The video became an immensely popular Internet meme, resulting in cover versions by John Mayer and Green Day drummer Tré Cool. The portion of the song in which Zonday turns away from the microphone, with a caption stating "I move away from the mic to breathe in", became an oft-repeated meme on 4chan and inspired remixes.
Catherine "Catie" Wayne, better known as the character Boxxy, is an American Internet celebrity known for her highly energetic vlogs. Her rise to exposure began in late 2008 and early 2009, surrounding self-made videos that were initially made to be posted to her Gaia Online profile. They then spread to 4chan and other sites, resulting in a large online following.
In his American incarnation, Pedobear is an anthropomorphic bear child predator that is often used within the community to mock contributors showing a sexual interest in children. Pedobear is one of the most popular memes on non-English imageboards, and has gained recognition across Europe. In February 2010, a photoshopped version of Pedobear appeared along with mascots of the 2010 Winter Olympics in an article on the games in Gazeta Olsztyńska, a Polish newspaper. This was done accidentally; due to the image being used from Google Images, the authors were unaware of the joke. Similarly, the Dutch television guide Avrobode used one of the images. It has been used as a symbol of pedophilia by Maltese graffiti vandals prior to a papal visit.
According to the Washington Post, "the site's users have managed to pull off some of the highest-profile collective actions in the history of the Internet."
Users of 4chan and other websites "raided" Hal Turner by launching DDoS attacks and prank calling his phone-in radio show during December 2006 and January 2007. The attacks caused Turner's website to go offline. This cost thousands of dollars of bandwidth bills according to Turner. In response, Turner sued 4chan, 7chan, and other websites; however, he lost his plea for an injunction and failed to receive letters from the court.
KTTV Fox 11 aired a report on Anonymous, calling them a group of "hackers on steroids", "domestic terrorists", and collectively an "Internet hate machine" on July 26, 2007. Slashdot founder Rob Malda posted a comment made by another Slashdot user, Miang, stating that the story focused mainly on users of "4chan, 7chan and 420chan". Miang claimed that the report "seems to confuse /b/ raids and motivational poster templates with a genuine threat to the American public", arguing that the "unrelated" footage of a van exploding shown in the report was to "equate anonymous posting with domestic terror".
On July 10, 2008, the swastika CJK unicode character (卐) appeared at the top of Google's Hot Trends list—a tally of the most popular search terms in the United States—for several hours. It was later reported that the HTML numeric character reference for the symbol had been posted on /b/, with a request to perform a Google search for the string. A multitude of /b/ visitors followed the order and pushed the symbol to the top of the chart, though Google later removed the result.
Later that year, the private Yahoo! Mail account of Sarah Palin, Republican vice presidential candidate in the 2008 United States presidential election, was hacked by a 4chan user. This followed criticism of Palin and other politicians supposedly using private email accounts for governmental work. The hacker posted the account's password on /b/, and screenshots from within the account to Wikileaks. A /b/ user then logged in and changed the password, posting a screenshot of his sending an email to a friend of Palin's informing her of the new password on the /b/ thread. However, he forgot to blank out the password in the screenshot. A multitude of /b/ users attempted to log in with the new password, and the account was automatically locked out by Yahoo!. The incident was criticized by some /b/ users, in that most reports on the hack focused on 4chan, rather than Palin's violation of campaign law. One user commented, "seriously, /b/. We could have changed history and failed, epically." The FBI and Secret Service began investigating the incident shortly after its occurrence. On September 20 it was revealed they were questioning David Kernell, the son of Democratic Tennessee State Representative Mike Kernell.
The stock price of Apple Inc. fell significantly in October 2008 after a hoax story was submitted to CNN's user-generated news site iReport.com claiming that company CEO Steve Jobs had suffered a major heart attack. The source of the story was traced back to 4chan.
In May 2009, members of the site attacked YouTube, posting pornographic videos on the site. A 4chan member acknowledged being part of the attack, telling the BBC that it was in response to YouTube "deleting music". In January 2010, members of the site attacked YouTube again in response to the suspension of YouTube user lukeywes1234 for failing to meet the minimum age requirement of thirteen. The videos uploaded by the user had apparently become popular with 4chan members, who subsequently became angered after the account was suspended and called for a new wave of pornographic videos to be uploaded to YouTube on January 6, 2010. Later the same year, 4chan made numerous disruptive pranks directed at singer Justin Bieber.
In September 2010, in retaliation against the Bollywood film industry's hiring of Aiplex Software to launch cyberattacks against The Pirate Bay, Anonymous members, recruited through posts on 4chan boards, subsequently initiated their own attacks, dubbed Operation Payback, targeting the website of the Motion Picture Association of America and the Recording Industry Association of America. The targeted websites usually went offline for a short period of time due to the attacks, before recovering.
A number of law firms associated with the anti-piracy industry were also affected, most notably the UK law firm ACS:Law, who had their web host account suspended multiple times due to the excessive traffic caused by the attacks.[unreliable source?] In retaliation for the initial attacks being called only a minor nuisance, Anonymous launched more attacks, bringing the site down yet again. After coming back up, the front page accidentally revealed a backup file of the entire website, which contained over 300 megabytes of private company emails, which were leaked to several torrents and across several sites on the Internet. It has been suggested that the data leak could cost the law firm up to £500,000 in fines for breaching British Data Protection Laws. in January 2011, BBC News reported that the law firm have announced they are to stop "chasing illegal file-sharers". Head of the ACS:Law Andrew Crossley in a statement to a court addressed issues which influenced the decision to back down "I have ceased my work...I have been subject to criminal attack. My e-mails have been hacked. I have had death threats and bomb threats."
On October 18, 2006, the Department of Homeland Security warned National Football League officials in Miami, New York City, Atlanta, Seattle, Houston, Oakland, and Cleveland about a possible threat involving the simultaneous use of dirty bombs at stadia. The threat claimed that the attack would be carried out on October 22, the final day of the Muslim holy month of Ramadan. Both the FBI and the Department of Homeland Security expressed doubt concerning the credibility of the threats, but warned the relevant organizations as a precaution. The games proceeded as planned but under a higher level of security awareness. The threats came to light in the national media after Jake Brahm admitted to having posted the threats on 4chan and repeating them on other websites approximately 40 times. Brahm did not expect the message to be taken seriously since he "would never take anything posted on 4chan as fact"; an FBI official was quoted as saying the "credibility of [the threat] was beyond ridiculous". As a parody of the incident, 4chan temporarily added "Don't mess with football" as an additional rule for /b/.
On September 11, 2007, at 9:11 am Central time, two pipe bombs will be remote-detonated at Pflugerville High School.Promptly after the blast, I, along with two ther Anonymous, will charge the building, armed with a Bushmaster AR-15, IMI Galil AR, a vintage, government-issue M1 .30 Carbine, and a Benelli M4 semi auto shotgun."
—The Pflugerville threat
On October 20, 2006, Brahm turned himself in to federal authorities, and was charged with fabricating a fake terrorist threat and taken into custody. On February 28, 2008, he pled guilty to the federal charges. On June 5, 2008, he was sentenced to six months in prison, six months' house arrest, and ordered to pay $26,750 in restitution.
Around midnight on September 11, 2007, a student posted photographs of mock pipe bombs and another photograph of him holding them while saying he would blow up his high school—Pflugerville High School in Pflugerville, Texas—at 9:11 am on September 11. Users of 4chan helped to track him down by finding the perpetrator's father's name in the Exif data of a photograph he took, and contacted the police. He was arrested before school began that day. The incident turned out to be a hoax; the "weapons" were toys and there were no actual bombs.
On January 21, 2014, an anonymous poster started a thread on /b/ identifying a student named Westley Sullivan who apparently went to the same high school as the poster. The original post included a link to Westley Sullivan's facebook profile, which has since been taken down, and a screenshot of a post which said "if fairview isnt closed tomorrow im going to blow it up", referring to Sullivan's high school, Fairview High School in Fairview, Kentucky. A few anonymous individuals went to Sullivan's facebook profile and found his address, phone number, school ID number, school schedule and teachers, and other personal information. Information like his teachers and ID number had been posted directly, and the more personal information like his address was found in the EXIF data of some of the pictures posted on his profile. These individuals then contacted Fairview school officials and the local police department, as well as the FBI. The next day it was learned that police had arrested Sullivan in his home and he had been charged with 2nd degree terroristic threatening, a Class D felony in Kentucky. 
Jarrad Willis, a 20-year-old from Melbourne, Australia was arrested on December 8, 2007, after apparently posting on 4chan that he was "going to shoot and kill as many people as I can until which time I am incapacitated or killed by the police". The post, accompanied by an image of another man holding a shotgun, threatened a shopping mall near Beverly Hills. While the investigation was still open, Willis was charged with criminal defamation for a separate incident but died before the case was heard.
On February 4, 2009, a posting on the 4chan /b/ said there would be a school shooting at St Eskils Gymnasium in Eskilstuna, Sweden. 1250 students and 50 teachers were evacuated. A 21-year-old man was arrested after 4chan had provided the police with the IP address of the poster. According to the police the suspect said it was a joke and he was released after they found no indication that the threat was serious.
On February 15, 2009, two videos featuring the physical abuse of a domestic cat named Dusty by a person calling himself "Timmy" were posted on YouTube. The 4chan community was able to track down the originator of the videos, a fourteen-year-old from Lawton, Oklahoma, and passed his details to his local police department. As a result of this, a suspect was arrested and the cat was treated by a veterinarian and taken to a safe place.
After 4chan reported a 15 year old boy in California who posted child pornography, the United States Department of Homeland Security raided his home on June 7, 2011 and took all electronic items.
On November 29, 2010, Ali Saad, aged 19, had his home raided by the FBI for posting child porn and death threats on 4chan. He was then arrested. Ali had only first visited 4chan just "a week before everything happened [the FBI raid]". He admitted to downloading about 25 child pornography images from 4chan.
On February 17, 2012, Thaddeus McMichael was arrested by the FBI for child pornography charges, after posting comments on Facebook claiming that he possessed child pornography. According to the official criminal complaint filed against Thaddeus, he admitted to obtaining child pornography from the /b/ board on 4chan.
On July 26, 2009, AT&T's DSL branch temporarily blocked access to the img.4chan.org domain (host of /b/ and /r9k/), which was initially believed to be an attempt at Internet censorship, and met with hostility on 4chan's part.
On July 27, 2009, AT&T issued a statement claiming that the block was put in place after an AT&T customer was affected by a denial-of-service attack originating from IP addresses connected to img.4chan.org, and was an attempt to "prevent this attack from disrupting service for the impacted AT&T customer, and... our other customers." AT&T maintains that the block was not related to the content on 4chan.
4chan's founder Christopher Poole responded with the following:
In the end, this wasn't a sinister act of censorship, but rather a bit of a mistake and a poorly executed, disproportionate response on AT&T's part. Whoever pulled the trigger on blackholing the site probably didn't anticipate [nor intend] the consequences of doing so. We're glad to see this short-lived debacle has prompted renewed interest and debate over net neutrality and Internet censorship—two very important issues that don't get nearly enough attention—so perhaps this was all just a blessing in disguise.
Major news outlets have reported that the issue may be related to DDoSing of 4chan and that the suspicions of 4chan users fell on the person who owned Swedish-based Anontalk.com at that time for doing this.
Concerning the AT&T claims of DDoS attacks originating from 4chan, Poole confirmed it was due to a network error:
For the past three weeks, 4chan has been under a constant DDoS attack. We were able to filter this specific type of attack in a fashion that was more or less transparent to the end user. Unfortunately, as an unintended consequence of the method used, some Internet users received errant traffic from one of our network switches. A handful happened to be AT&T customers
On February 4, 2010, 4chan started receiving reports from Verizon Wireless customers that they were having difficulties accessing the site's image boards. After investigating, Poole found out that only traffic on port 80 to the boards.4chan.org domain was affected, leading members to believe that the block was intentional. On February 7, 2010, Verizon Wireless confirmed that 4chan was "explicitly blocked". The block was lifted several days later.