Tempus Labs is where Chicago’s modern unicorn era really starts. Founded in 2015 with the vision of using data and AI on clinical and molecular information to improve cancer care, the company crossed the billion-dollar mark in 2018. This was not a consumer app or a daily-deals site. It was deep, defensible technology in a hard, science-heavy field, and it proved that Chicago could build and fund something like that.

Standing on earlier shoulders

Tempus did not appear from nowhere. Chicago had already built a track record that made investors comfortable: Groupon went public in 2011, Grubhub grew into a household name, and Braintree was acquired by PayPal in 2013. That earlier generation proved Chicago founders could build and exit successfully, seeding the local capital and talent that the next wave would draw on. Tempus founder Eric Lefkofsky was himself a veteran of that scene, a serial founder who had already been part of Groupon, and he brought that experience into healthcare, where the ambition was considerably harder.

Why Tempus mattered

The company reached unicorn status in 2018, and it stood out as the marquee name of that moment because it was solving something genuinely difficult. By integrating vast amounts of medical data with AI to personalize cancer treatment, it was doing the kind of work that takes years to prove out and is hard to replicate. Unlike the flash-in-the-pan categories that dominate tech cycles, precision medicine in oncology has compounding value: the more data Tempus collected, the harder its position became to challenge. Tempus eventually went public on Nasdaq in 2024, closing the loop from startup to public company.

The bigger picture

Tempus fits the thesis I keep returning to: Chicago wins by building substantive companies in real industries rather than chasing hype. It is the healthcare cousin of the city’s applied-AI scene, and it is an early data point in the argument that Chicago is a serious AI hub, one grounded in the steady strength of the city’s broader tech ecosystem.

If you want to understand the boom that hit Chicago in 2021, you have to start in 2018 with Tempus. It was proof of concept for the whole city: build something hard, build it here, and the billion-dollar valuations will follow. The flood of unicorns a few years later did not come out of nowhere. Tempus showed the door was open.