SOURCES: This Ex-Googler Is About To Sell His Ad Tech Company For $175 Million To $200 Million

How's this for a nice start to the decade?

Back in 2010, Jason Kelly quit Time Inc and the old media world to join a digital advertising startup called Admeld as Chief Revenue Officer.

That move paid off big time when, in 2011, Admeld sold to Google for $400 million.

Then, in 2012, Kelly quit Google to run another digital advertising startup. He became CEO of Sociomantic.

Sociomantic, founded in Berlin, is what's known in the industry as a "demand side platform," or "DSP." That means ad agencies can use it to buy ads across many publishers and networks of publishers around the world.

We've learned from a pair of industry sources that Kelly is about to cash-in again.

This source tells us that Kelly has sold Sociomantic to Dunnhumby, a subsidiary of Tesco. The price, we're told, is between $175 million and $200 million. We corresponded with a second industry source who confirmed the news.

A note of caution about this story: We heard this information from two industry sources who are not Dunnhumby or Sociomantic employees. Also, the deal isn't final yet, and things sometimes fall apart.

We've spoken to spokespeople at Dunnhumby and Sociomantic. So far, both have declined to comment. Our source says the news will break as early as this week.

Online advertising is a rapidly evolving industry and it seems like new startups never stop sprouting up and getting consolidated. It also feels like it's the same group of people doing it over and over.

What's really interesting about Kelly's career is that, according to his LinkedIn page, he was advancing very quickly in the world of airline industries from 1999 to 2007.

The move to Time Inc was his first job in media. Sometimes people are reluctant to switch industries. Obviously it can pay off.