On Tuesday, they got some satisfaction in France: an injunction was issued against the gossip magazine that put pictures of a topless Duchess of Cambridge on view for all to see.
While that means the publisher was supposed to hand over digital copies of photos snapped by a photographer with a very long lens in Provence, it hardly resolves the larger question of just how much privacy a royal — or anyone, for that matter — can expect in this era of instant internet communication.
And how, ultimately, can whatever privacy laws that do exist be fully enforced?
"You can go to court, you can get, as they've done, an injunction and that can prevent future publication by that magazine," says Kirsty Hughes, a lecturer and expert in privacy law at the University of Cambridge's Clare College in the U.K.
"But it's very difficult to stop something once it's actually out and it's already online, so to some extent it’s a limited remedy."
An injunction can send a legal signal to publications that might consider publishing risky material, but if a person's privacy has already been violated, it's a genie that really can't be put back in the bottle.
"It's something which can't really be compensated for fully in the same way that we can compensate for other things like defamation, where it can be corrected," says Hughes, who notes that in a global era of online communication, it's much more problematic.
Diana and Caroline
While the photos that are at the heart of the current controversy focus — at least fuzzily — on Prince William's wife, Kate, the spectre of two other royal women haunts the current quandary.
One of those women is Diana, William's mother, who died in a car crash while fleeing paparazzi in Paris in 1997. The other is Princess Caroline, now married to Prince Ernst of Hanover, but who was born Princess Caroline of Monaco.
In the 1990s, Caroline took great umbrage with pictures published in German publications of her in places that would generally be considered public, such as restaurants or a beach club.
She took her case to the German courts, but didn't get the resolution she wanted. That led her to the European Court of Human Rights, where in 2004, it was found that publication of some pictures violated Caroline's right to respect for private life under Article 8 of the European Convention on Human Rights.
"The European court in that case held that this was a violation of Article 8, that … although these might be seen as photos in a public place, the princess still had a reasonable expectation of privacy and this had been violated by the press," says Hughes, who notes the case is a "direct precedent" for the proceedings surrounding the Duchess of Cambridge.
Diana's shadow looms even larger over the current controversy, something not unnoticed by the British media that has so far resisted publishing any photos of a topless Kate. Politically, they know, any appearance of those pictures in a U.K. paper would not wash with the public.
"I think there's a strong amount of sympathy for the Duke and Duchess of Cambridge, as Princess Diana died in car accident fleeing the paparazzi," says Carolyn Harris, a Toronto-based royalty expert who has a blog on the topic.
"Even though there were other factors as well in [Diana's] death — the driver had been drinking — there was a real sense that the paparazzi had contributed to her death, so in a way the public is more protective of the younger royals."
Kate is hardly the first royal to face controversy over privacy, or seek legal remedy. Diana and Prince Charles went to the lawyers, too.
In the case of Charles, Kate's father-in-law and the heir to the throne, Harris says the most significant instance involves journals he kept at the time of the handover of Hong Kong to China in 1997.
"He made some very critical comments about China and Chinese leadership in those journals and they were circulated to a small group of 50 people," says Harris. "A former employee of his leaked them to the … Mail on Sunday and so it became a debate over the prince's privacy."
In the end, Charles won.
"Ultimately it was judged in Prince Charles's favour that these were his private journals, that the handover of Hong Kong was a public event but the keeping of these journals was a private pastime, so that set some precedents in terms of the Royal Family having the right to some degree of private life outside their public duties," says Harris.
In another recent royal dustup over privacy, Buckingham Palace contacted Britain's Press Complaints Commission.
Pictures of William's brother Harry cavorting naked in a Las Vegas hotel room spread like wildfire online.
But that situation was different from the one surrounding Kate, suggests Alanna Glicksman, a Toronto-based public relations consultant and entertainment blogger.
Living in a social world
"He was in a hotel room with females he invited in to party with him, whereas Kate was with her husband in a secluded house that belonged to a member of the family and she was not inviting this attention."
The nature of the world we live in, where everything seems to merit a tweet or some other form of online sharing, is also at play, she says, noting how every moment of William and Kate's current Asian tour is documented online.
"The world we live in right now is very social and people like to share and this idea of privacy is blurred in many parts of our lives, not just with the royals. Everything becomes fair game because it's so easy to share what's happening," Glicksman says.
"We're able to see so far into their lives that it's almost hard for people to draw a distinction when we're crossing that line of privacy."
So then ultimately, what right and expectation of privacy exists?
"Ultimately anybody can invade anybody's privacy," says Robert Currie, director of the law and technology institute at the Schulich School of Law at Dalhousie University in Halifax
"You could be in a walled compound, but I could fly over with a helicopter and take pictures of you. Does that mean you weren't entitled to expect a bit of privacy in your walled compound? No. Most reasonable people would say you were and that it was unduly invasive for me to fly over with a helicopter just to take pictures of you."
For Currie, the question of whether privacy laws work is a good one, but one that's too big to answer.
In society's best interest
"You'd have to try to measure it quantitatively."
As a society, he says, we have an interest in there being effective privacy laws.
Currie will be watching as the Kate case proceeds, and looking at what happens around various publications of the photos, including in an Italian magazine that ran the pictures on Monday.
"That illustrates the interesting push and pull in our society today, which is this idea that if I have information, I should be able to publish it.
"But when that information concerns another person, there are legal restrictions. Where … the boundaries are is constantly being redrawn."
Also on HuffPost