By Thomas Bernal, VP Go To Market, Ogury
When Netscape engineer Lou Montulli invented the cookie in 1994, he could have never expected it would become the lynchpin of targeted advertising for decades. These tiny pieces of code let Montulli create shopping carts that remembered what items consumers had placed inside. Still, it didn’t take long for advertisers to realise cookies left digital footprints that could be pieced together to target and retarget individuals across the web.
Now, cookies are teetering on the edge of obsolescence, one of many changes in the past few years that has made “signal loss” — where once-reliable signals for user and audience characteristics have been eroded by the prioritisation of data privacy — a top concern for consumers, that soon filtered through to digital advertisers and publishers.
To understand how we got here and what’s next, let’s explore how, in just a few short years, the digital advertising ecosystem went from knowing far too much about consumers to realising that the best way to learn about audiences might be to simply ask.
2017: Apple gets the privacy ball rolling
Apple’s Intelligent Tracking Protection (ITP) was the company’s first major swing at establishing its reputation as a privacy champion, which it has only built upon since. ITP is a feature built into Apple’s browser Safari, designed to stop advertisers from tracking users’ activities across different websites, preventing data signals from one domain being used to inform targeted advertising on another.
This triggered a game of cat and mouse between Apple and adtech vendors: every time the latter would figure out a loophole to track Safari users, the former would close it up with an update. Apple has continued to curtail advertisers’ ability to track its users ever since.
2018–2019: Regulators bring down the hammer
By 2018, public concern about data privacy had reached its boiling point, as large-scale leaks and data harvesting scandals filled the headlines. In response, regulations — such as the EU’s General Data Protection Regulation (GDPR) and the California Consumer Privacy Act (CCPA) — ushered in an industry-wide data privacy paradigm shift.
Companies had to reevaluate how they collected and leveraged user data, building in consent opt-ins from the jump and then tracking this consent — and allowing for its withdrawal — wherever the data travelled. This remains a challenge today.
GDPR served as a template for data privacy regulations that have since sprung up across the globe and laid the groundwork for the privacy-focused advertising ecosystem we know today. However, the fundamentals of targeting and tracking remained unchanged as long as third-party cookies remained the most accessible and viable audience signal.
2020: Google digs a grave for cookies, but doesn’t fill it
In 2020, Google accelerated the disappearance of identifiers when it announced it would phase out third-party cookies in Chrome, by far the biggest browser in terms of market share. Initially, the timeline was two years, but Google delayed cookie deprecation multiple times in response to industry feedback and the need to refine their replacement solutions.
Regardless, the announcement lit a fire under the advertising industry to develop and integrate advertising solutions that didn’t rely on third-party cookies. In particular, publishers have prioritised collecting first-party data from their audiences and platforms to mitigate the addressability shortfall.
2021: Apple lets users say no to tracking, and they do
Apple landed a decisive blow against behavioural advertising with the launch of its App Tracking Transparency (ATT) framework in 2021. ATT requires users to explicitly consent to any tracking across apps and websites, including when using Apple’s own IDFA (Identifier for Advertisers) — the olive branch it offered to advertisers when it stripped cookies from its ecosystem with ITP.
The signal loss was profound: following its launch, approximately 80% of users opted out of tracking, significantly reducing the volume of addressable audiences for iOS-based advertising.
2021–now: Google plays around in the Privacy Sandbox
Google’s position in the ecosystem — with Chrome accounting for 65% of browser market share — has prevented it from deprecating cookies without offering an alternative: the Privacy Sandbox. Still under development, this collection of browser-based initiatives aims to balance user privacy with the needs of advertisers to target valuable audiences.
In mid-2024, Google finally pivoted from this initial plan to an “updated approach that elevates user choice”, which has been broadly interpreted as an ATT-like opt-in method, though there has been no further clarification on what this means at the time of writing.
If we work with the assumption that Chrome will have a cookie opt-in mechanism, it is estimated that only 17% of users will do so. Between this tiny sliver of “cookied” Chrome users and the cookieless browsers that make up the rest of the market, this would leave just 13% of open web audiences addressable via traditional targeting methods.
Cookies, once the king of scale, will be relegated to a footnote in the far more varied data portfolio of the privacy-first future.
An industry scrambling for a shrinking pool of addressable audiences
The shrinking pool of addressable audiences resulting from ongoing signal loss has created immense friction for both sides of the digital advertising supply chain.
This decline has made it significantly harder for publishers to monetise their ad spaces due to the lack of data. As for advertisers, they favour ID-based inventories — which are becoming increasingly scarce — and are consequently faced with higher costs.
Industry players must stop putting their targeting eggs in one basket. No one solution — whether cookies, alternative IDs, contextual data, and so on — can provide enough scale in isolation to accurately represent the breadth and depth of open web audiences. Strategies and solutions must be more bespoke and hybridised to maximise reach and precision.
Consumer participation is the future of a fair and transparent data market
Since 2017, accelerating signal loss has forced the digital advertising industry to do more with less. By moving away from the hyper-personnalisation made possible by an overabundance of personal data, the advertising industry has been forced to return to its fundamentals. Brands have relied on panels to understand their consumers since the early days of marketing. Today, this methodology can be repurposed to collect data that is independent of advertising identifiers.
This has led to a resurgence in tried and tested data collection methods that fell out of favour during the Wild West days of invasive tracking and eerily precise targeting. Surveys and online panels — under the umbrella of zero-party data — render privacy concerns obsolete by having consumers directly share information about their interests, preferences, attitudes, and intentions. It’s like asking someone if they are planning on buying a car in the next twelve months, rather than trying to predict it by analyzing their online behaviour.
There are widespread fears that signal loss will result in less efficient advertising campaigns, but at a time when data minimisation, supply chain optimisation, and CO2 reduction are top priorities, data provided by users themselves delivers a closer relationship to consumers with minimal waste, while also fostering trust and transparency.
Combining old-school approaches to data collection with cutting-edge statistical modelling gives the best of both worlds between detail and scale while creating a data market where people are active participants rather than unwitting — and, often, unwilling — data mules. Why search for signals in a sea of noise when you can get data of substance directly from the source?
