The Robinhood tracking site Wall Street is obsessed with was built by a college senior as a side project

• Robintrack has become Wall Street's favorite site for Robinhood data, as analysts and investors gauge what role retail trading has played in the market's recent rally from March lows.
• Casey Primozic built the site two years ago when he was a senior at Valparaiso University in Indiana, Bloomberg reported on Wednesday.
• Starting in late April, traffic to the site exploded, jumping from about 4,000 unique visitors per day to anywhere between 20,000 and 50,000 per day, Primozic told Bloomberg.
• Read more on Business Insider.

In just two years, Robintrack went from being a college senior's side project to the top site where Wall Street firms, hedge funds, and institutional investors get data for Robinhood, the popular trading app.

Casey Primozic, 23, built the site in 2018 during his final year at Valparaiso University in Indiana, Bloomberg reported on Wednesday. Starting in late April, traffic to the site exploded, jumping from about 4,000 unique visitors per day to anywhere between 20,000 and 50,000 per day, Primozic told Bloomberg.

Robintrack's popularity has been boosted in recent months as Wall Street tries to gauge the impact of retail investors in the market's rally following the coronavirus-induced meltdown and March lows. The site, which is not affiliated with Robinhood, uses the popular app's stock-ownership data for insights into what retail investors are holding and trading.

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Lately it's been called upon as retail investors pile into "odd" trades such as snapping up shares of bankrupt companies like Hertz and JCPenney. Analysts at Barclays used Robintrack to show that Robinhood investors were not behind the stock market's recent rally, while analysts at Societe Generale cheered the "impeccable" timing of those same investors.

Primozic told Bloomberg that there were signs that major hedge funds including D. E. Shaw & Co. and Point72 were either looking at or directly collecting data from Robintrack. He also said he could hardly keep up with his overflowing email inbox, full of advertiser pitches and messages from Wall Street banks about how they can legally use the data on his site.

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"To be clear, that's totally fine with me. I allow the data I collect to be used freely for any purpose," he told Bloomberg. "It was neat to see that the institutional investors are interested in the data just the same as everyone on Twitter."

Primozic has also had a brush with Robinhood itself because of the site, the report said: A recruiter for Robinhood reached out to Primozic after the site went live in May 2018, and the company flew him to California for a job interview.

But he didn't get the job, Primozic told Bloomberg. He now lives in Seattle and works as a software developer for an early-stage startup, the report said.

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