What you need to know
- Mozilla has shared a new look at Apple's Private Click Measurement.
- PCM is supposed to help advertisers get the information they need while preventing tracking.
- Mozilla believes that the system isn't worth the trade-off.
Mozilla, the company behind the popular Firefox web browser, has slammed a Safari privacy feature and dubbed it "a poor trade-off between user privacy" and the functionality needed by web advertisers.
Apple's Private Click Measurement (PCM) feature was introduced last year and is designed to allow websites and ad companies to keep track of clicks and conversion without giving them unfettered access to all of the data that can also be used to track people from one website to another. But Mozilla says that the way in which it does that causes its own problems that don't necessarily prevent tracking while making it more difficult for advertisers to get the information they need.
PCM is already available as part of iOS 15, but it needs websites to use its API in order to function. Mozilla explains how PCM is supposed to work in Safari right now:
As fine as that sounds, an in-depth report claims that the mechanisms used by PCM aren't sufficient to protect users in the ways Apple is trying to, while making it more difficult for advertisers and removing any incentive for web publishers to use it.
- Although PCM prevents sites from performing mass tracking, it still allows them to track a small number of users. -The measurement capabilities PCM provides are limited relative to the practices that advertisers currently employ, with long delays and too few identifiers for campaigns being the most obvious of the shortcomings.
In fact, Mozilla goes so far as to say that if Firefox included support for PCM in lieu of its own Toral Cookie Protection, it would actually make it less private.
Mozilla includes various examples of why it believes PCM isn't all it's cracked up to be and the longer report is well worth reading.
Finally, Mozilla wraps its blog post up with a damning sentence that sums things up pretty succinctly:
Apple's privacy stance has long been a strong one and Safari is one area where it continues to try to ensure advertisers and data brokers are unable to follow us around the internet. Apple would likely argue that preventing ad companies from tracking conversion as well as they would like is a trade-off it is willing to make, but web publishers won't implement its PCM API if they don't have to — and that trade-off could well mean that they won't.
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Oliver Haslam has written about Apple and the wider technology business for more than a decade with bylines on How-To Geek, PC Mag, iDownloadBlog, and many more. He has also been published in print for Macworld, including cover stories. At iMore, Oliver is involved in daily news coverage and, not being short of opinions, has been known to 'explain' those thoughts in more detail, too.
Having grown up using PCs and spending far too much money on graphics card and flashy RAM, Oliver switched to the Mac with a G5 iMac and hasn't looked back. Since then he's seen the growth of the smartphone world, backed by iPhone, and new product categories come and go. Current expertise includes iOS, macOS, streaming services, and pretty much anything that has a battery or plugs into a wall. Oliver also covers mobile gaming for iMore, with Apple Arcade a particular focus. He's been gaming since the Atari 2600 days and still struggles to comprehend the fact he can play console quality titles on his pocket computer.