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Could I have seen the adverts?

“You could have, you could have,” says Hitesh Chawla.

What are those brands, if you could name them?

In his dimly lit glass cabin on the third floor of a mall in Gurugram, Chawla, co-founder of SilverPush, a company which sells technology solutions to target consumers with ads across television and digital media, hesitates slightly. “I am not sure if I should share names.”

“I can tell you one,” he then continues. “They were a large e-commerce company called They aren’t in business, so I can tell you. They were a big client.”

In 2014, the e-commerce company was running ads starring the Bollywood actors Ranbir Kapoor and, later, Kangana Ranaut, Askme’s still-available profile on YouTube shows. Askme, connected to the Malaysian billionaire Ananda Krishnan, shut shop in 2016. Chawla says the company still owes him half a million dollars.

Either of those adverts on TV may have emitted an ultrasonic audio beacon, an identifier embedded in the television signal, using sound close to or beyond the human hearing capability. If you were watching it and your mobile had an app using SilverPush’s software development kit (SDK), it would have promptly pinged the company’s server.

Unbeknownst to the mobile user, this allowed SilverPush and its clients to know which of its adverts were being watched in the vicinity of the device. What’s more, unlike electromagnetic waves used, for example, in Bluetooth, ultrasonic sound waves cannot pass through walls. This can let you precisely determine a device’s location. The aim, at the time, was to have more granularity and real-time data on television viewers by connecting an offline and an online device.  

"We were reaching two to three million mobiles in India"

Hitesh Chawla

Chawla, 36, comes across as charming in an earthy way. Dressed in a blue sweater, jeans and light shoes with streaks of grey in his curly hair, he later breaks our conversation to take a call in animated, laughing Punjabi. A 2004 batch IIT Delhi chemical engineer who was born near the India border, and spent years in research in Australia, he doesn’t appear to be the stereotypical villain.

Not long ago though, for US privacy groups and tech media, he was.

Things fall apart

It was between October 2015 and March 2016 that SilverPush’s audio beacon model came apart. To follow the trail of events is an object lesson in how the interconnected world operates.

Referencing newspaper reports from the US media and India, the Washington-based Center for Democracy and Technology had written to the US Federal Trade Commission (FTC) in October 2015, in anticipation of a workshop on cross-device tracking.


Virat Markandeya

Virat Markandeya is an independent journalist based in Delhi. He has written on science and technology for publications like IEEE Spectrum, Nautilus and the Nature Publishing Group. He is most inspired while hearing the clangs of history in academic papers. His motto is Pauca Sed Matura and he tweets at @viratmarkandeya.

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