He is one of a number of high-profile individuals bringing privacy claims against the publisher over allegations it carried out or commissioned illegal or unlawful information-gathering. See his arrival at court on Monday here...
This included the hiring of private investigators to place listening devices inside cars, the 'blagging' of private records and the accessing and recording of private phone conversations.
Now Harry has spoken about the impact of such "unlawful acts" and the impact it had on his teenage years.
In a document filed on Harry’s behalf, barrister David Sherborne said: "In particular, suspicion and paranoia was caused by Associated's publication of the unlawful articles: friends were lost or cut off as a result and everyone became a 'suspect' since he was misled by the way that the articles were written into believing that those close to him were the source of this information being provided to Associated's newspapers."
He added: "The claimant regards Associated's unlawful acts to amount to a major betrayal given promises made by the media to improve its conduct following the tragic and untimely death of his mother, Princess Diana, in 1997."
Harry, Sir Elton John, his husband David Furnish, Baroness Doreen Lawrence of Clarendon and Sadie Frost all attended the Royal Courts of Justice on Monday for the start of the first hearing in their claims against Associated Newspapers Limited (ANL).
The group also includes Elizabeth Hurley and former Lib Dem MP Sir Simon Hughes.
Other allegations disclosed for the first time on Monday included claims that Sir Elton and Mr Furnish's landline at their home in Windsor was tapped.
Mr Sherborne said: "They are also mortified to consider all their conversations, some of which were very personal indeed, were tapped, taped, packaged and consumed as a commercial product for journalists and unknown others to pick over, regardless of whether or not they were published."
Lawyers for ANL, which is also the publisher of The Mail On Sunday and MailOnline, said the allegations are "firmly denied" and that the "stale" claims have been brought too late as it made a bid to throw out the cases.
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