Consumer rights advocates have launched a class action lawsuit against Google, claiming the biz took millions of iPhone users' personal information illegally.
The campaign, dubbed Google You Owe Us, is led by former Which? executive director Richard Lloyd.
It focuses on the revelation that, in 2011 and 2012, Google bypassed the privacy settings on Apple's iPhone Safari browser to track people's online activity.
The Chocolate Factory's business model is predicated on selling this personal data to advertisers, but the group said that users needed to trust that this data is slurped in a "fair and lawful" way.
By bypassing Safari privacy settings, it said Google breached the trust of 5.4 million UK users, while making billions from selling targeted advertising.
"In all my years speaking up for consumers, I've rarely seen such a massive abuse of trust where so many people have no way to seek redress on their own," said Lloyd.
He added that this was "the first case of its kind in the UK against a major tech company for misusing our valuable personal data".
The action is seeking compensation for those people based on infringement of data protection rights and loss of control of data, which normally brings damages of less than £1,000.
But the group stressed that the case goes "beyond financial motivations" as it will "make an example of one of the world's biggest companies".
The groundwork for this class action suit was set by a 2015 case, brought by three people who claimed their privacy rights had been breached by the Safari workaround. The Court of Appeal of England and Wales ruled that users could sue the Mountain View giant in the UK.
However, as the group points out, it's not possible for most people to bring cases against megabucks firms, making representative action the only sensible way forward.
The cost of the case – filed in London's High Court and due for hearing in early 2018 – including insurance in case Lloyd loses is being covered by a litigation funding group, Therium.
Everyone who was affected will be automatically included in the case, and if it's successful they will be asked to prove this – such as by showing they had an Apple ID at that time – in order to receive a payout*.
People who don't want to be involved – for instance if they want to bring a separate claim for misuse of private information that caused more harm – can opt out.
Peter Vicary-Smith, chief executive of consumer rights group Which?, welcomed the campaign, saying that people had to put their trust in big corps because of the increasingly large role they play in everyone's day-to-day lives.
"To have this good faith rewarded by Google taking advantage of people's information without their consent is something that rightly must be challenged."
The lawsuit follows news that privacy campaigner Max Schrems has launched a nonprofit to enforce European citizens' privacy rights under the incoming General Data Protection Regulation, which allows NGOs to campaign on behalf of others.
*You can claim if, at any time between June 1, 2011 and February 15, 2012 you: had an Apple ID, lawfully owned an iPhone, used Safari to get online, kept the default browser security settings and did not opt out of tracking and collation via Google's ad preference manager. Oh, and you also have to have been resident in England or Wales on May 31, 2017.
Updated to add 17.06
A Google spokesperson told The Register: "This is not new – we have defended similar cases before. We don't believe it has any merit and we will contest it."