Guy Krief

I co-founded Persado and Bryq, ran Upstream as CEO across 45 markets, and now invest in early stage tech at Big Pi Ventures. I also wrote an award-winning documentary that exposed ad fraud by running a real fraud operation.

Currently Partner at Big Pi Ventures in Athens, €250M under management, backing deep-tech and B2B founders across Europe. I sit on the boards of Nutropy, Juisci and Bryq. I'm also president of La French Tech Athens, which connects the Greek and French ecosystems.

In 2012 I co-founded Persado in New York, one of the first large-scale generative language platforms. CNBC Disruptor 50, running in production at companies like Verizon, Skype, American Express and JPMorgan Chase. I also co-founded Bryq, which uses psychometrics and machine learning for hiring, now used by hundreds of companies including EY and Mercedes-Benz. Inventor on five granted patents in AI language generation and ad-fraud detection.

Was CEO of Upstream from 2017 to 2020. 300+ people, seven offices, 45 markets, more than a billion consumers. We built an anti-ad-fraud platform that now protects over 500 million mobile users. Previously on the boards of Upstream, Convert Group and LSPR.

I wrote and co-produced Unclickable, a documentary on digital ad fraud. To show how the money moves, we built our own fraud operation, fake sites and bot traffic, and took real money from real advertisers. It premiered at Thessaloniki in 2024 and Seattle in 2025.

Before that, I created and hosted a comedy show on Greek television. I'm an investor in Nolan, a Michelin awarded restaurant in Athens.

I spoke at TEDxPatras in 2022, on transformation and the power of boring.

French, based in Athens, working in English, French and Greek. MA Social Psychology, Paris V Sorbonne, 1999.