The publisher of The Mail On Sunday has lost a Court of Appeal challenge against a ruling in favour of the Duchess of Sussex over publication of a personal letter to her estranged father, Thomas Markle.

Meghan, 40, sued Associated Newspapers Limited (ANL), also the publisher of MailOnline, over five articles that reproduced parts of a “personal and private” letter to Thomas Markle, 77, in August 2018.

The duchess won her case earlier this year when a High Court judge ruled in her favour without a full trial.

ANL brought an appeal against that decision and, at a three-day hearing in November, argued the case should go to a trial on Meghan’s claims against the publisher – including breach of privacy and copyright.

Lawyers representing the publisher said at the earlier hearing that Mr Markle wished to counter points made by friends of Meghan who had given an interview to People magazine in the US.

But, in a ruling on Thursday, Sir Geoffrey Vos, Dame Victoria Sharp and Lord Justice Bean dismissed the publisher’s appeal.

Reading a summary of their decision, Sir Geoffrey said: “It was hard to see what evidence could have been adduced at trial that would have altered the situation.

“The judge had been in as good a position as any trial judge to look at the article in People magazine, the letter and The Mail On Sunday articles to decide if publication of the contents of the letter was appropriate to rebut the allegations against Mr Markle.

“The judge had correctly decided that, whilst it might have been proportionate to publish a very small part of the letter for that purpose, it was not necessary to publish half the contents of the letter as ANL had done.”

In a statement after the ruling, Meghan said: “This is a victory not just for me, but for anyone who has ever felt scared to stand up for what’s right.

“While this win is precedent setting, what matters most is that we are now collectively brave enough to reshape a tabloid industry that conditions people to be cruel and profits from the lies and pain that they create.

“From day one, I have treated this lawsuit as an important measure of right versus wrong. The defendant has treated it as a game with no rules.

“The longer they dragged it out, the more they could twist facts and manipulate the public (even during the appeal itself), making a straightforward case extraordinarily convoluted in order to generate more headlines and sell more newspapers — a model that rewards chaos above truth.

“In the nearly three years since this began, I have been patient in the face of deception, intimidation and calculated attacks.

“Today, the courts ruled in my favour — again — cementing that The Mail on Sunday, owned by Lord Jonathan Rothermere, has broken the law.”

The judges were told during the hearing that 585 out of 1,250 words had been republished in the five articles.

Meghan’s barristers argued the letter was “deeply personal” and “self-evidently was intended to be kept private”.

In her written evidence, Meghan denied she thought it likely that her father would leak the letter, but “merely recognised that this was a possibility”.

Jason Knauf, former communications secretary to the Duke and Duchess of Sussex, claimed in a witness statement that Meghan wrote the letter with the understanding that it could be leaked.

He said she sent him an early draft of the letter and had written: “Obviously everything I have drafted is with the understanding that it could be leaked so I have been meticulous in my word choice, but please do let me know if anything stands out for you as a liability.”

In further texts released by the court, the duchess can be seen expressing her frustration about the response of the royal family, describing them as “constantly berating” Harry.

The Court of Appeal also heard that Mr Knauf provided information to the authors of the biography Finding Freedom – Omid Scobie and Carolyn Durand – leading to Meghan apologising for misleading the court about whether he had given information.