Data privacy

Data privacy: your browsing habits can be exposed 1000 times a day


Author: Sergio van Pan

Web browsers are a two-way communication means: you read websites, and websites read you. The number of data harvesters is constantly growing and this makes privacy concerns as topical as never before. While many website trackers can be blocked (read more on Sidekick’s commitment to privacy) others operate behind the scenes and secretly track everything you are looking at, no matter how sensitive it is. The scale of this clandestine operation is now measured. And the results are a bit shocking.

The widespread online advertising system RTB – Real-Time-Bidding – is “the biggest data breach ever recorded”, according to a new report by the Irish Council for Civil Liberties (ICCL).

RTB is an advertising technology that companies use to compete for ad space on the websites you visit. It’s a millisecond-long automated auction that shares your private data, including location and browsing habits. This sharing of data is called RTB broadcast.


“It tracks and shares what people view online and their real-world location 294 billion times in the U.S. and 197 billion times in Europe every day,” ICCL says. This data privacy report is based on confidential data obtained from a source.

On average, U.S. citizens have their online activity and location exposed 747 times every day by the RTB system. Record 987 daily RTB broadcasts per person were registered in Colorado, U.S.

U.S. citizens have their data exposed 57% more often than people in Europe because of privacy regulation differences.

RTB data privacy concerns have been raised many times in the past, especially in Europe.

About 6,000 firms receive RTB data from Google, which is the biggest RTB company.

The RTB industry generated $117 billion in the U.S. and Europe in 2021.

“Real-Time Bidding operates behind the scenes on websites and apps. It tracks what you are looking at, no matter how private or sensitive, and it records where you go. Every day it broadcasts this data about you to a host of companies continuously, enabling them to profile you,” the report says.

There is no way to restrict the use of RTB data after it is broadcast, the report says.

The figures presented for RTB broadcasts are a low estimate, according to the report. “The industry figures on which we rely do not include Facebook or Amazon RTB broadcasts.”