We are Sift Science. We do trust.

Unfortunately, evil exists. Fortunately, we're here to stop it! Fraud and abuse plague online businesses of all types, from marketplaces to payment processors, social networks to e-commerce stores. As the internet's trust layer, Sift Science's mission is simple yet powerful: make these online experiences faster, smoother, and safer – using the smartest technology around.

Up, up and away!

Risk scores per day



Domains protected

Learning speed



Events analyzed per day

Launched in 2011 from the Y Combinator incubator program, Sift Science has grown into the leading machine learning fraud detection solution for online businesses. Every day, thousands of websites and apps rely on our cloud-based machine learning to eliminate fraud, slash costs, and grow revenue. And we're just getting started.

Meet the team.

With leaders hailing from Google, Amazon, Zillow, Twilio, and New Relic, the Sift Science team has decades of experience building teams and technology, scaling startups, and solving the internet's toughest problems.

A software engineer at heart, Jason was an early engineer at a few Seattle startups (Zillow, Optify, BuzzLabs), before migrating to San Francisco to start Sift Science in 2011. He enjoys chess, basketball, and freestyle rapping.

Jason Tan


Fred loves building well-designed, robust, scalable systems. Before Sift, he was a tech lead at Google, Principal Engineer at Jambool, CTO at Teachstreet, product lead at Zillow and engineer at Amazon.

Fred Sadaghiani


Zee loves building customer bases and partnerships for global cloud businesses. Prior to Sift he led sales at Twilio, and business development for EC2 at Amazon Web Services.

Zeeshan Yoonas

Head of Sales

Liz focuses on the most critical asset of an organization - its people. She has startup experience in Technical Recruiting and People Ops and is pursuing her MS from Northwestern in I-O Psychology and Coaching.

Liz Kosinski

Head of People Operations

A team builder, problem solver, avid traveler and proud mother, Karen held executive roles at Google in Operations, Strategic Partnerships and Finance. A former management consultant, she has an MBA from Yale.

Karen Tsay

Head of Business Operations

Thomas loves building products that solve critical business problems. Typical enterprise software shenanigans are his mortal enemy. Prior to Sift, Thomas worked at Twilio, AdMob and Google.

Thomas Schiavone

Head of Product

Passionate about building high performance teams, Toshi ran engineering at several high-growth startups as CTO & VP Engineering. Prior to helping startups, he held engineering roles at Oracle and holds a CS degree from Princeton.

Toshinari Kureha

Head of Engineering

Our believers.

  • Max Levchin

    PayPal Co-founder

  • Marc Benioff

    Salesforce.com CEO

  • Chris Dixon

    Andreessen Horowitz Partner

Like what you see? Join the team!

We're building an incredible machine learning, big data, cloud, SaaS company in the heart of San Francisco. But hey - we're not all about buzzwords. We're also about defeating evil and making the internet a safe place for everyone!

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