Case study · 2006 · filed 24 September 2026

Searcher No. 4417749

In 2006 AOL published 20 million search queries with the names swapped for numbers. Within days, reporters found the woman behind one of them.

The DÆTRAX team · privacy research

In August 2006 AOL released about 20 million search queries for researchers to study. The names were gone. Each person was a number.

The New York Times took one number, 4417749, and read what it had searched for: "numb fingers", "60 single men", "dog that urinates on everything", and local businesses in one town. From those alone, reporters found Thelma Arnold, a 62-year-old widow in Lilburn, Georgia. She confirmed the searches were hers.

What it shows

Taking the name off doesn't make data anonymous. What you search for, where you go and what you write describe you well enough that someone can find you from them. That was true of one newspaper reading by hand in 2006, and it's cheaper now.

For your own record

When a company says it shares your data "anonymised" or "de-identified", ask who received it and ask them to stop. We wrote about why that promise has worn thin in De-identified does not mean what it used to.

Start your record

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