A Northampton University student is standing trial after allegedly assisting Anonymous in cyberattacks against firms including PayPal and MasterCard.
"Operation Payback" began as a digital assault within the music industry, where hacktivist collective Anonymous targeted companies and organisations who declared themselves against piracy. However, once a number of firms began refusing to process payments and donations to whistleblower website WikiLeaks in 2010, the collective's attention turned to these companies in revenge.
PayPal suffered the brunt of this campaign, but MasterCard, Visa, the Ministry of Sound and the International Federation of the Phonographic Industry (IFPI) were also hit. Distributed denial of service (DDoS) attacks were used to overload systems with requests.
The BBC reports that in court the jury was told that Anonymous hackers cost PayPal £3.5 million ($5.5m) after the campaign, as the firm was forced to pull staff from parent company eBay to work on issues relating to the security breach for weeks afterwards, and PayPal was forced to purchase additional software and hardware to secure itself against future attacks.
At the time, PayPal said Wikileaks breached its user policies, which prevent its services from being used to "support criminal activity." Funds were later unfrozen.
Due to the attack, the prosecution, Mr Patel, argued that PayPal suffered "enormous economic harm," as well as damage to the company's reputation.
The 22 year-old Northampton University student, Christopher Weatherhead, allegedly was part of the attacks.
Weatherhead has denied all charges of conspiracy, pleading not guilty of conspiring to impair the operation of computers between 1 August 2010 and 22 January 2011. Three other men stand accused of taking part.
Mr Patel said Weatherhead "played a central and integral role in the overall effectiveness" of the Anonymous campaign, telling jurors: