Wall Street Fixates on a College Side Project Tracking Robinhood

Two years ago, Casey Primozic was wrapping up his undergraduate years at Valparaiso University in Indiana. He was also building a website -- for fun. Little did he know it would grow into a Wall Street obsession.

Now in 2020, his college side project, Robintrack.net, has seen site traffic explode as everyone from day traders to institutions flock there for a picture of what retail investors are buying. Primozic says there’s evidence hedge funds are scraping his data. The 23-year-old programmer can hardly keep up with an overflowing email inbox and is getting barraged with pitches from advertisers.

“I’ve...