Stewart Butterfield and Joel Greenblatt built their fortunes in very different corners of business. Butterfield became a major technology entrepreneur through Flickr and Slack, while Greenblatt established himself as a respected value investor through Gotham Capital and his influential investment books. Both followed unconventional paths and turned their expertise into long-term success. Butterfield’s wealth is tied largely to technology and Slack, while Greenblatt’s fortune comes from investing, asset management, and decades of financial experience.
Stewart Butterfield and Joel Greenblatt Quick Bio
| Detail | Stewart Butterfield | Joel Greenblatt |
|---|---|---|
| Full Name | Daniel Stewart Butterfield; born Dharma Jeremy Butterfield | Joel Greenblatt |
| Date of Birth | March 21, 1973 | December 13, 1957 |
| Net Worth | About $1.6 billion (Forbes real-time estimate, Sept. 2026) | Estimated around $500 million; exact personal wealth is not publicly disclosed and published estimates vary |
| Age | 53 | 68 |
| Birthplace | Lund, British Columbia, Canada | Great Neck, New York, USA |
| Nationality | Canadian | American |
| Profession | Entrepreneur, technology executive, designer and investor | Investor, hedge-fund manager, author, educator and businessman |
| Famous For | Co-founding Flickr and Slack; former CEO of Slack | Founding Gotham Capital, developing the “Magic Formula” investment approach and writing books on value investing |
| Parents | David and Norma Butterfield are reported in biographical sources; detailed family information is limited | Parents’ full names are not reliably documented in major public sources |
| Siblings | Not reliably documented | Not reliably documented |
| Education | University of Victoria, B.A. in Philosophy; University of Cambridge, M.Phil. in Philosophy | University of Pennsylvania Wharton School — B.S. and MBA; briefly attended Stanford Law School |
| Career Beginning | Worked in programming and design before launching technology ventures | Entered investment management and founded Gotham Capital in 1985 |
| Major Companies/Firms | Ludicorp, Flickr, Tiny Speck, Slack Technologies, Salesforce | Gotham Capital, Gotham Asset Management |
| Flickr Connection | Co-founded Flickr, which was later acquired by Yahoo | No direct connection |
| Slack Connection | Co-founder and former CEO of Slack; Salesforce acquired Slack for $27.7 billion in 2021 | No direct connection |
| Investment Career | Primarily technology entrepreneurship and investments | Value investing and special-situation investing |
| Gotham Capital | No connection | Founded Gotham Capital in 1985, the predecessor to Gotham Asset Management |
| Current Professional Role | Technology entrepreneur/investor; no longer CEO of Slack | Managing Principal and Co-Chief Investment Officer of Gotham Asset Management |
| Writing & Books | Known mainly for technology products and entrepreneurship | Author of You Can Be a Stock Market Genius, The Little Book That Beats the Market, The Little Book That Still Beats the Market, The Big Secret for the Small Investor and Common Sense |
| Teaching | Not primarily known as an academic | Longtime adjunct professor at Columbia Business School, teaching value and special-situation investing |
| Known Investment Philosophy | Technology, product design and entrepreneurship | Value investing, special situations and the Magic Formula |
| Height | Around 5 ft 10 in (178 cm), reported/unverified | Around 5 ft 8 in (173 cm), reported/unverified |
| Weight | Not reliably documented | Not reliably documented |
| Hair Color | Brown, reported/observed | Gray/white, reported/observed |
| Eye Color | Brown, reported/observed | Brown, reported/observed |
| Marital Status | Married; personal-life details are relatively private | Married; personal-life details are largely private |
| Children | Public sources differ on the number; Forbes lists 1 in its personal profile | Children’s details are not reliably documented in major public sources |
| Residence | Aspen, Colorado, according to Forbes | New York area is associated with his professional and personal history |
| Hobbies/Interests | Technology, design, photography, online communities and entrepreneurship | Investing, education, philanthropy and financial research |
| Philanthropy | Has supported technology and community-related causes | Co-founder of Success Academy Charter Schools and involved with University of Pennsylvania and education-related initiatives |
| No account confidently verified from authoritative sources | No account confidently verified from authoritative sources | |
| Business Style | Product-focused, creative and technology-driven | Research-driven, analytical and value-oriented |
| Major Achievement | Helped create two influential internet products: Flickr and Slack | Built a highly regarded investment career and popularized value-investing concepts for ordinary investors |
| Estimated Wealth Source | Slack/Salesforce proceeds, investments and technology ventures | Investment-management success, personal investments and long-term capital growth |
| Public Profile | High-profile Silicon Valley entrepreneur | Prominent but comparatively private Wall Street investor and author |
| Legacy | Helped shape online photo sharing and workplace communication | Made sophisticated value-investing ideas more accessible to individual investors |
Stewart Butterfield and Joel Greenblatt Images
