Mozilla Asks: Will Google's Privacy Sandbox Protect Advertisers (and Google) More than You?

On Mozilla's blog, engineer Martin Thomson explores Google's 'Privacy Sandbox' initiative (which proposes sharing a subset of private user information — but without third-party cookies).

The blog post concludes that Google's Protected Audience 'protects advertisers (and Google) more than it protects you.' But it's not all bad — in theory:

The idea behind Protected Audience is that it creates something like an alternative information dimension inside of your (Chrome) browser... Any website can push information into that dimension. While we normally avoid mixing data from multiple sites, those rules are changed to allow that. Sites can then process that data in order to select advertisements. However, no one can see into this dimension, except you. Sites can only open a window for you to peek into that dimension, but only to see the ads they chose...
Protected Audience might be flawed, but it demonstrates real potential. If this is possible, that might give people more of a say in how their data is used. Rather than just have someone spy on your every action then use that information as they like, you might be able to specify what they can and cannot do. The technology could guarantee that your choice is respected. Maybe advertising is not the first thing you would do with this newfound power, but maybe if the advertising industry is willing to fund investments in new technology that others could eventually use, that could be a good thing.

But here's some of the blog post's key criticisms:

'[E]ntities like Google who operate large sites, might rely less on information from other sites. Losing the information that comes from tracking people might affect them far less when they can use information they gather from their many services... [W]e have a company that dominates both the advertising and browser markets, proposing a change that comes with clear privacy benefits, but it will also further entrench its own dominance in the massively profitable online advertising market...'

'[T]he proposal fails to meet its own privacy goals. The technical privacy measures in Protected Audience fail to prevent sites from abusing the API to learn about what you did on other sites.... Google loosened privacy protections in a number of places to make it easier to use. Of course, by weakening protections, the current proposal provides no privacy. In other words, to help make Protected Audience easier to use, they made the design even leakier...'

'A lot of these leaks are temporary. Google has a plan and even a timeline for closing most of the holes that were added to make Protected Audience easier to use for advertisers. The problem is that there is no credible fix for some of the information leaks embedded in Protected Audience's architecture... In failing to achieve its own privacy goals, Protected Audience is not now — and maybe not ever — a good addition to the Web.'

Read more of this story at Slashdot.