Which AI model is the best trader? Finance professor says he has the answer.

Humanoid robot stands on a stock exchange trading floor surrounded by market data screens and Citadel Securities displays.

Dr. Alejandro Lopez Lira has been trying to prompt AI chatbots to beat the market since 2023.

Lopez Lira, an associate professor of finance at the University of Florida, began his project early in the AI boom to see which model could trade stocks to deliver market-beating returns. After almost three years of testing the most popular models, he said he’s got his answer.

“DeepSeek is by far the best trader,” he told Business Insider.

DeepSeek’s portfolio is up 73% since it launched in 2023 and 35% year-to-date. ChatGPT has slightly outpaced DeepSeek since launch, up 78%, but is only up 16% year-to-date. The Grok portfolio has returned 54% since inception and 19% year-to-date.

He said DeepSeek is also beating Claude, though he noted that Anthropic’s chat bot hasn’t been managing a portfolio for as long as the others.

Can DeepSeek beat the market? Our public experiment during the past year says yes: up 76% against 27% for the S&P 500.

$13.5M in client capital, 2,285 subscribers, every position live and public.

See it all and trade alongside here: https://t.co/e88z6qTdC8 pic.twitter.com/HVUGeVBPBX

— AI Finance Labs (@aifinancelabs) May 28, 2026

All of his AI-managed portfolios can be publicly viewed on Autopilot, an app that allows retail traders to copy moves made by successful investors, from Warren Buffett to Nancy Pelosi investors. Copy trading has become popular in recent years, and, according to Autopilot co-founder Chris Josephs, there has been increasing interest among users in copying trades made by AI-run stock portfolios.

“What’s fascinating is we see people apply and want to launch more and more funds, launch more and more portfolios, and more people are using AI to essentially prompt out their ideas,” he told Business Insider.

Lopez Lira said that while each AI model functions similarly in terms of information processing, he estimated that they only make the same calls about 50% of the time.

“There’s some setup involved in the sense that you have to add the latest information to the model — firm news, various fundamentals, things like that — but the final decision is the model’s completely.”

In a GPT portfolio white paper shared on his Autopilot page, Lopez Lira provided examples of some of the prompts he’s used in setting up the portfolio.

Document exhibit shows a firm prompt for generating investment reports and scores from financial data.

The platform also shows lists of recent trades each AI portfolio has made. Most recently, it shows 19 trades made by DeepSeek on July 14, including increasing its position in Nvidia and reducing its Vista Energy holdings.

While Micron Technology is the top holding for both DeepSeek and Grok’s portfolios, the second-highest performing portfolio, ChatGPT, favors Kratos Defense & Security Solutions, a lesser known aerospace recently named as a top pick by Stifel.

While the Claude portfolio also holds Kratos stock, its top holding is the iShares 0-3 Month Treasury Bond ETF, a stark contrast to the other bot’s preferences for Big Tech and energy stocks. It also maintains a fairly large position in Vista Energy, a contrarian position relative to DeepSeek’s move to reduce its position.

Samuel O’Brient is an experienced financial markets and business journalist who has written extensively on a wide range of topics involving economics, technology and public policy. At Business Insider, he covers important macro and micro economic stories, including takes from leading economists and hedge fund managers, breaking IPOs, corporate bankruptcies, meme stocks and short-selling. He also writes on other markets such as crypto, oil and real estate.He has interviewed many of the market’s most influential voices, ranging from top economists such as Mark Zandi and Richard Thalerto prominent investors including Danny Moses, Andrew Left, Anthony Scaramucci, Louis Navellier and Grant Cardone.Programs such as LiveNOW from Fox , Taking Stock and Ticker News have had Samuel on to discuss stock market and economic developments. His reporting has been cited by The New York Times DealBook, Bloomberg Radio, Forbes, Entrepreneur, Gizmodo and TheFutureParty.Samuel began at InvestorPlace, covering investing, retail trading and macro economic trends. Prior to joining Business Insider, he served as a technology markets reporter at TheStreet. He is a graduate of Sarah Lawrence College and Trinity College Dublin.Samuel’s work has appeared in publications such as TipRanks, EV and Observer. When he isn’t chasing down stories, he can often be found browsing book and record shops. To reach Samuel, email him at sobrient@insider.com or connect with him on LinkedIn. He is also on Signal as Samuel Clemens. Popular Articles: A Nobel economist has a warning for meme stock tradersThe business school dropout who kicked off the Beyond Meat rally wants you to know he’s not Roaring Kitty 2.0 A top economist who thinks we’re on the brink of a recession says he’s eyeing these 3 warning signs Trump’s 401(k) executive order marks big changes for retirement savings — and possibly puts your money at risk Why hedge fund icon Ray Dalio says you shouldn’t invest in real estate in this economy AI bullishness is soaring, but pros see a major opportunity brewing in an overlooked corner of the market