• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
Finance

‘Big Short’ investor Michael Burry returns to Twitter to warn about passive investing

By
Declan Harty
Declan Harty
Down Arrow Button Icon
By
Declan Harty
Declan Harty
Down Arrow Button Icon
September 20, 2021, 11:35 AM ET

One of the most famous short-sellers of the 2008 financial crisis is back online, tweeting about the markets.

Michael Burry, whose credit-default-swap trade against the housing market brought him fame by way of Michael Lewis’s book The Big Short, returned to Twitter over the weekend after a months-long hiatus. The head of Scion Asset Management doubled down on his long-standing concerns about the rise of passive investing, citing a recently released working paper that found the stock market’s aggregate value tends to rise by about $5 for every $1 invested.

https://twitter.com/michaeljburry/status/1439629962424717313

For years, investors on both Wall Street and Main Street have been throwing money into passive investment strategies like exchange-traded funds—hoping to capitalize on the belief that no one can consistently beat the market. There was a record $9.73 trillion of assets invested through ETFs, as well as exchange-traded products, globally at the end of August, marking a 21.8% jump from the end of 2020, according to research and consultancy firm ETFGI.

The flood of money into passive investing has come after years of stock pickers, by and large, failing to beat out the rest of the market. Earlier this year, S&P Dow Jones Indices found about 75% of large-cap funds in the U.S. underperformed the S&P 500 over the trailing five years leading up to the end of 2020.

Burry has long seen a bubble, though. In 2019, the hedge fund manager equated the swarm of money that has hit index funds to the rise of collateralized debt obligations in the lead-up to the financial crisis. “Like most bubbles, the longer it goes on, the worse the crash will be,” Burry said in an email exchange with Bloomberg at the time.

“The first step is to recognize that 5:1 is not a natural ratio,” Burry tweeted Sunday. “So what will continue this paradigm? What may reverse it? This is the knife’s edge, BECAUSE we are at 5:1. It may go to 100:1. Or become -5:1. But parabolas don’t resolve sideways.”

Passive investment vehicles are not the only part of today’s markets that are showing signs of a bubble in Burry’s eyes, though. In June, before deleting his tweets and quitting Twitter, Burry warned of “the mother of all crashes” that could come from investors throwing their money into cryptocurrencies and meme stocks. And in the second quarter, Burry also made a handful of bets against the ETFs of Cathie Wood’s ARK Invest, which are not passively managed.

On Saturday, in a since deleted tweet, Burry called for a boycott of Big Tech, while linking to the Wall Street Journal’s recent series, The Facebook Files. Scion held $327.3 million of call options on Facebook at midyear, according to its latest quarterly filing.

“Whether a little or a lot, please do,” Burry said. “For your health and the health of others.”

More finance coverage from Fortune:

  • Months after the SPAC boom, returns have been “weak,” says Goldman Sachs
  • Should remote employees earn less? Most employers say no
  • Lumber’s epic boom and bust, explained in 8 charts
  • China’s “COVID-zero” policy hit its economy in August. Now a new Delta outbreak poses another threat
  • NYSE’s new investment vehicle—”natural asset companies”—will tap into ESG fever

Subscribe to Fortune Daily to get essential business stories straight to your inbox each morning.

About the Author
By Declan Harty
See full bioRight Arrow Button Icon

Latest in Finance

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Leadership
  • Success
  • Tech
  • Asia
  • Europe
  • Environment
  • Fortune Crypto
  • Health
  • Retail
  • Lifestyle
  • Politics
  • Newsletters
  • Magazine
  • Features
  • Commentary
  • Mpw
  • CEO Initiative
  • Conferences
  • Personal Finance
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map

Latest in Finance

trump
Economynational debt
The $38 trillion national debt is one thing 82% of Americans agree on: ‘Voters are understandably concerned,’ watchdog says
By Nick LichtenbergJanuary 7, 2026
3 hours ago
Real EstateHousing
Americans missed out on a ‘once-in-a-lifetime’ chance to buy a house—the 3 shifts it would take to make housing affordable are ‘very unlikely’
By Sydney LakeJanuary 7, 2026
4 hours ago
Donald Trump speaks into a microphone
PoliticsDonald Trump
Trump’s Greenland takeover would require ‘billions upon billions’ spent over decades to acquire a mineral industry that doesn’t yet exist, experts say
By Lily Mae LazarusJanuary 7, 2026
4 hours ago
Larry Page looks up and to the right.
InvestingBillionaires
Jensen Huang might be fine with a billionaires tax, but Google cofounder Larry Page is already dumping California
By Sasha RogelbergJanuary 7, 2026
4 hours ago
middle
Future of WorkJobs
Top economist says latest jobs data shows a ‘jobless expansion’ with no historical precedent—and it’s ‘gut-wrenching’ for the middle class
By Eva RoytburgJanuary 7, 2026
6 hours ago
CryptoBitcoin
‘There’s so much corruption, embezzlement and missing money’: Venezuela’s rumored $60 billion Bitcoin ‘shadow reserve’ draws skepticism
By Jake AngeloJanuary 7, 2026
6 hours ago

Most Popular

placeholder alt text
Law
Amazon is cutting checks to millions of customers as part of a $2.5 billion FTC settlement. Here's who qualifies and how to get paid
By Sydney LakeJanuary 6, 2026
1 day ago
placeholder alt text
Economy
Mark Cuban on the $38 trillion national debt and the absurdity of U.S. healthcare: we wouldn't pay for potato chips like this
By Nick LichtenbergJanuary 6, 2026
1 day ago
placeholder alt text
Personal Finance
Janet Yellen warns the $38 trillion national debt is testing a red line economists have feared for decades
By Eva RoytburgJanuary 5, 2026
2 days ago
placeholder alt text
Future of Work
'Employers are increasingly turning to degree and GPA' in hiring: Recruiters retreat from ‘talent is everywhere,’ double down on top colleges
By Jake AngeloJanuary 6, 2026
1 day ago
placeholder alt text
Success
The college-to-office path is dead: CEO of the world’s biggest recruiter says Gen Z grads need to consider trade and hospitality jobs that don't even require degrees
By Orianna Rosa RoyleJanuary 6, 2026
1 day ago
placeholder alt text
Success
Blackstone exec says elite Ivy League degrees aren’t good enough—new analysts need to 'work harder' and be nice 
By Ashley LutzJanuary 5, 2026
2 days ago

© 2025 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.