How was it allowed to happen? What action can the Palace take? Multiple questions were common place on social media and nationwide.
To get an expert's legal view on the matter, Digital Spy spoke to Hearst Magazines UK media lawyer, Charlotte Jackson.
How is the magazine allowed to publish pictures from what is a clear invasion of privacy?
"Closer magazine in France was not 'allowed' to publish the topless photographs of the Duchess of Cambridge. Privacy laws in France are notoriously strict and often favour protecting the private lives of public officials. For example, the existence of former President Francois Mitterrand's second family was only divulged to the public with his approval just before his death.
"It is highly likely that these photographs were published in breach of French privacy law - they are intimate photographs taken in a private place and reportedly with a long lens. However, the magazine will probably have weighed up the financial benefit of publishing them against the potential financial risk for doing so.
"It is estimated that Closer may be fined in the region of €30,000 (£24,000) for publishing the photographs and we suspect they anticipate making considerably more in sales revenue, making it worth their while, financially, to take the risk."
What legal options do Kate and William have? Especially given that the magazine is French and the pictures are now all over the internet.
"On the basis that the photographs are of a very personal nature and were taken on private property with a long lens, the Duchess of Cambridge could sue for breach of privacy. The claim would have to be brought in the French courts on the basis that the photographs were published by a French publication in France. The Duchess is internationally recognised as a prominent public official and as such would certainly have sufficient status to bring a privacy claim in the French courts.
"St James's Palace has already issued a statement confirming that the Duke and Duchess are considering their legal options and that they have been angered and saddened by these events."
Could they sue the publisher or the photographer? Wouldn't the photographer be arrested if he did this to a "normal" woman?
"The Duchess of Cambridge could sue the publisher for publishing the photographs in breach of her privacy. The photographer has not been named but if the Duchess could establish who had taken them and where they were taken she may have a claim, not for breach of privacy, but for trespassing if the photographer was on the private property when taking the photographs. If the photographs were taken by a member of staff it is likely that they would be dismissed.
"As above, the photographs were taken and published in France so any claim would have to be brought in the French courts.
"Financially, it may not be worth bringing a claim against the photographer. It would be more beneficial to sue the publisher. To do so successfully may send a strong message to the publishing industry about the Duke and Duchess's views regarding their privacy and how they intend to deal with breaches of privacy. If damages were awarded, the Duchess may choose donate them to a charity of her choosing as people have done in the past."
How much were the shots likely to have sold for?
"We can't be sure how much the photographs would have sold for. Presumably less than the expected fine to make it worthwhile for the magazine to buy them, but they may have been less expensive than we think. There is likely to have been a limited market for them. The general feeling seems to be that the publication of these photographs has been in bad taste and certainly in breach of French privacy law. Many publications may have considered the reputational and legal risks to outweigh the financial ones in this case."
What would happen if a UK publication printed the same images?
"Despite the recent photographs of Prince Harry published by The Sun, it is unlikely that the UK press would have bought and published these photographs. The UK media has a very good relationship with the royal family recently, particularly with the Duke and Duchess of Cambridge all of whom have been very open with the media.
"Publishing these photographs in the UK would certainly have ostracised the relevant publishing house from the royal family and could have been very damaging to a magazine's reputation. The public were very supportive of Prince Harry following The Sun's publication of photographs of him and it is likely the British public would have been as if not more so in this case."
Does the images being available uncensored on the very international world wide web make a mockery of the whole concept of a national Press Complaints Commission?
"No. The fact that the world wide web makes images like these globally available does not make a mockery of national guidelines regarding publishing content of this nature. Nation States still have local laws, regulations and guidelines that are relevant to and apply to those jurisdictions specifically. The PCC provides guidance about publishing content in the UK and that remains relevant for magazines and newspapers published in the UK.
"That said, it is important to remember that the PCC provides guidance regarding content. It is not a regulator and it does not protect principles that are enshrined in law. When content is published in breach of a person's privacy it is the law that is broken and the courts that you would look to to enforce that. Not the PCC.
"It may be that the increasing power of the world wide web to immediately spread content globally raises questions about international guidelines for publishers, but in reality it would take a long time to change such guidelines and if you could agree them and apply them at European or international level, you would then have to consider who would police them and how."
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