Selling fake Twitter followers now generates up to an estimated $360 million per year.
There are an estimated more than 20 million fake Twitter accounts, created by more than two-dozen services that sell buy phony followers to Twitter users. An increased follower count could give a Twitter user a veneer of greater popularity or importance.
Two Italian researchers who presented their findings to The New York Times estimated that phony follower services generate $360 million per year.
The Italian researchers who helped shed light on the phenomenon of fake Twitter followers have also discovered that Facebook link spam now generates an average of $200 million per year.
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Source: en.wikipedia.org
It’s estimated that Twitter itself will generate slightly less than $310 million in mobile revenue in 2013. (The company is estimated to generate more than $580 million overall in 2013.)
Phony Twitter followers were first highlighted in 2012 when Mitt Romney’s follower count rose dramatically in a short period. A number of services, such as TwitterAudit.com, have been developed to estimate how many of a given Twitter account’s followers are fake.

UK TV network Channel 4 will air on Aug. 5 an investigation into “click farms,” where teams of low-paid workers, typically located in the developing world, attempt to fake the popularity of content online. Workers earn as little as $120 per year “liking” online content.
Of 974 million Twitter accounts, about 44% have never tweeted, according to an April report from Twopcharts, which tracks Twitter account activity. Twitter said it had 241 million monthly active users — someone who logs in at least once a month, but who might not tweet — in the last quarter of 2013.
In a new filing with the SEC, Twitter says that “up to approximately 8.5%” of “active” accounts are updated automatically “without any discernible additional user-initiated action.” That means that potentially 23 million of Twitter’s 271 million monthly active users are bots, according to Quartz.