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

Trendingnow

1

The Bezos family just donated $100 million to help achieve one of Mayor Zohran Mamdani’s top campaign promises

2

Despite having a $165 million net worth, Scarlett Johansson says work-life balance doesn’t exist—and the first step to success is admitting that

3

Nearly 50,000 Lake Tahoe residents have to find a new power source after their energy source looks to redirect lines to data centers

1

The Bezos family just donated $100 million to help achieve one of Mayor Zohran Mamdani’s top campaign promises

2

Despite having a $165 million net worth, Scarlett Johansson says work-life balance doesn’t exist—and the first step to success is admitting that

3

Nearly 50,000 Lake Tahoe residents have to find a new power source after their energy source looks to redirect lines to data centers
InvestingMicrosoft

Bill Ackman has been quietly buying Microsoft since February, when AI fears were dragging the stock

By
Eva Roytburg
Eva Roytburg
Fellow, News
Down Arrow Button Icon
By
Eva Roytburg
Eva Roytburg
Fellow, News
Down Arrow Button Icon
May 15, 2026, 11:14 AM ET
US hedge fund manager Bill Ackman, CEO of Pershing Square Capital Management, speaks during the 29th annual Milken Institute Global Conference at the Beverly Hilton in Beverly Hills, California on May 4, 2026.
US hedge fund manager Bill Ackman, CEO of Pershing Square Capital Management, speaks during the 29th annual Milken Institute Global Conference at the Beverly Hilton in Beverly Hills, California on May 4, 2026. Patrick T. Fallon / AFP via Getty Images

Bill Ackman is going against the grain to back Microsoft.

Recommended Video

Pershing Square Capital Management, the hedge fund run by the billionaire investor, has built a new position in the software giant. 

And in typical Ackman fashion, he disclosed the stake in his trademark style: a lengthy post on X on Friday ahead of his firm’s quarterly 13F filing (a required filing for institutional investment managers with over $100 million in assets). He did not disclose the size, but called it a “core holding.”

Pershing started accumulating shares in February, after Microsoft’s stock fell about 10% the day after Q2 earnings, with a 1% lower-than-expected cloud growth alongside a surge in capital spending. “We were able to establish our position at a valuation of 21 times forward earnings, broadly in line with the market multiple and well below Microsoft’s trading average over the last few years,” Ackman wrote in the post.

Microsoft’s stock is down more than 15% year-to-date as it fights to prove that its Azure cloud business has enough revenue to justify its AI spending. The erosion of its partnership with AI, which was recently restructured to strip Microsoft of exclusive distribution rights, only furthered those concerns.

Ackman sees that restructuring as a pivot to a multi-model architecture that can better suit the needs of its enterprise customers.

He also argues that investors underestimate Microsoft’s 365 productivity suite and its stickiness, saying the suite is “deeply embedded” in enterprises and “nearly impossible to replicate,” he wrote.

Ackman pushed back on concerns over Microsoft’s $190 billion 2026 capex budget, arguing it as growth investment on a J curve rather than a threat to margins. He also pointed out that Microsoft’s market capitalization does not yet reflect its 27% economic interest in OpenAI— worth approximately $200 billion at the startup’s most recent funding round valuation, he said.

The Microsoft buy continues Ackman’s pattern of stepping into Big Tech during periods of AI-related skepticism.

“We acquired Alphabet when the stock declined substantially on the release of ChatGPT in late 2022, Amazon in the weeks following Liberation Day, and Meta more recently on the market’s response to the company’s unexpectedly large capex guidance,” he wrote.

The Fortune 500 Innovation Forum will convene Fortune 500 executives, U.S. policy officials, top founders, and thought leaders to help define what’s next for the American economy, Nov. 16-17 in Detroit. Apply here.
About the Author
By Eva RoytburgFellow, News
Instagram iconLinkedIn icon

Eva covers macroeconomics, market-moving news, and the forces shaping the global economy.

See full bioRight Arrow Button Icon

Latest in Investing

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
Fortune Secondary Logo
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • World's Most Admired Companies
  • See All Rankings
  • Lists Calendar
Sections
  • Finance
  • Fortune Crypto
  • Features
  • Leadership
  • Health
  • Commentary
  • Success
  • Retail
  • Mpw
  • Tech
  • Lifestyle
  • CEO Initiative
  • Asia
  • Politics
  • Conferences
  • Europe
  • Newsletters
  • Personal Finance
  • Environment
  • Magazine
  • 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
  • Group Subscriptions
About Us
  • About Us
  • Press Center
  • Work At Fortune
  • Terms And Conditions
  • Site Map
  • About Us
  • Press Center
  • Work At Fortune
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

Latest in Investing

US hedge fund manager Bill Ackman, CEO of Pershing Square Capital Management, speaks during the 29th annual Milken Institute Global Conference at the Beverly Hilton in Beverly Hills, California on May 4, 2026.
InvestingMicrosoft
Bill Ackman has been quietly buying Microsoft since February, when AI fears were dragging the stock
By Eva RoytburgMay 15, 2026
1 hour ago
Current price of Bitcoin for May 15, 2026
Personal FinanceCryptocurrency
Current price of Bitcoin for May 15, 2026
By Joseph HostetlerMay 15, 2026
3 hours ago
Current price of Ethereum for May 15, 2026
Personal FinanceEthereum
Current price of Ethereum for May 15, 2026
By Joseph HostetlerMay 15, 2026
3 hours ago
Chuck Robbins, chief executive officer of Cisco
InvestingFinance
‘Critical infrastructure for the AI era’: Cisco’s CEO on the earnings beat that sent shares to a record
By Sheryl EstradaMay 15, 2026
6 hours ago
Cerebras Systems ad on a billboard.
AIChips
Cerebras CEO says AI chip demand is ‘not speculative’ as shares double in blockbuster IPO debut
By Beatrice Nolan and Sharon GoldmanMay 14, 2026
23 hours ago
Top CD rates from major banks May 14, 2026: Chase CDs, Bank of America CDs, Citibank CDs, and more
Personal FinanceCertificates of Deposit (CDs)
Top CD rates from major banks on May 14, 2026: Chase CDs, Bank of America CDs, Citibank CDs, and more
By Joseph HostetlerMay 14, 2026
1 day ago

Most Popular

The Bezos family just donated $100 million to help achieve one of Mayor Zohran Mamdani’s top campaign promises
Politics
The Bezos family just donated $100 million to help achieve one of Mayor Zohran Mamdani’s top campaign promises
By Jake AngeloMay 12, 2026
3 days ago
Despite having a $165 million net worth, Scarlett Johansson says work-life balance doesn’t exist—and the first step to success is admitting that
Success
Despite having a $165 million net worth, Scarlett Johansson says work-life balance doesn’t exist—and the first step to success is admitting that
By Preston ForeMay 13, 2026
2 days ago
Nearly 50,000 Lake Tahoe residents have to find a new power source after their energy source looks to redirect lines to data centers
Travel & Leisure
Nearly 50,000 Lake Tahoe residents have to find a new power source after their energy source looks to redirect lines to data centers
By Catherina GioinoMay 12, 2026
3 days ago
The airplane fuel shortage is a myth propagated by airlines who want to cancel unprofitable flights, says private jet CEO
Energy
The airplane fuel shortage is a myth propagated by airlines who want to cancel unprofitable flights, says private jet CEO
By Jim EdwardsMay 14, 2026
1 day ago
Current price of oil as of May 14, 2026
Personal Finance
Current price of oil as of May 14, 2026
By Joseph HostetlerMay 14, 2026
1 day ago
Steve Jobs used a 'beer test' for interviews at Apple—if he didn’t want to drink with you, you didn’t get the job
Success
Steve Jobs used a 'beer test' for interviews at Apple—if he didn’t want to drink with you, you didn’t get the job
By Orianna Rosa RoyleMay 14, 2026
1 day ago

© 2026 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.