Jack Dorsey

Corporate hierarchy, Jack Dorsey argues, is a 2,000-year-old information-relay system, and artificial intelligence can now do the relaying. In April 2025 he cut Block's workforce by roughly 40 percent, moved from first exploration to announcement in under three weeks, and replaced the org chart with three roles.¹

Dorsey is a co-founder of Twitter, the short-message social network that became one of the world's dominant public communication platforms, and the founder and chief executive of Block (originally Square), a payments and financial-technology company. He is the only person to have founded two companies that have both been listed on the S&P 500.

Background

Dorsey was born on November 19, 1976, in St. Louis, Missouri; his father, Tim Dorsey, was an engineer who worked on mass spectrometers. As a child he was fixated on maps, trains, and city logistics, listening to police and taxi dispatch scanners; he has described a city as, in effect, a dispatch problem. He also stuttered and competed in oratory to work through it. When his father brought home an IBM computer around age 14, Dorsey began writing software, and by 15 had written open-source dispatch-routing software adopted by some taxi and courier companies.² He briefly attended the University of Missouri-Rolla before transferring to New York University, which he left one semester short of a degree. It was in New York that the idea behind Twitter, personal status broadcast the way a dispatcher broadcasts a vehicle's status, first took shape.

Getting started

At 19, before finishing college, Dorsey found a security vulnerability on a dispatch software company's website and emailed a description of the hole from an address crafted to look like it came from the company's own chairman. The company hired him about a week later, bringing him to New York. A later dispatch-and-payments venture with Greg Kidd, dNet.com, never gained traction, and after the dot-com bust Dorsey moved back to Missouri and worked odd jobs before later living in Kidd's backyard shed in Oakland. A chance meeting with Evan Williams led to a job at Williams's podcasting company, Odeo. When Apple's iTunes podcasting platform undercut Odeo's market in fall 2005, Williams held an internal hackathon, and Dorsey, with Biz Stone, Florian Weber, and Noah Glass, built a working prototype in about two weeks. That became Twitter. Dorsey posted the first message, "just setting up my twttr," on March 21, 2006, and became its first chief executive.²

What he built

Twitter grew into a global public messaging network built around short posts, initially capped at 140 characters, readable by anyone without a reciprocal social connection. It went public on the NYSE in November 2013, raising roughly 1.8 billion dollars. Dorsey was removed as CEO by Twitter's board in 2008 but returned to lead the company from 2015 to 2021, stepping down that November; Twitter was acquired by Elon Musk in October 2022.

In parallel, Dorsey co-founded Square in 2009 with Jim McKelvey, a friend and glassblower who had lost a sale for want of a way to accept a credit card. Square's first product was a small card reader that plugged into a smartphone's headphone jack, letting individuals and small merchants accept card payments without traditional merchant-processing infrastructure. Its underwriting model rejected the industry default of credit-check gatekeeping, instead onboarding broadly and monitoring transactions afterward, a change Dorsey has said sharply raised merchant acceptance rates.³ Square went public on the NYSE in November 2015 at 9 dollars a share, valuing it at roughly 2.9 billion dollars. It later launched Cash App, a peer-to-peer payments and banking app that grew to generate more than half of Block's business. In 2021 Square was renamed Block, an umbrella covering Square, Cash App, a majority stake in the music service Tidal, the Bitcoin unit then called TBD, and the self-custody wallet Bitkey. Block scaled back Tidal and wound down TBD in 2024 to focus on Bitcoin mining and Bitkey. In April 2025, Dorsey cut Block's workforce by roughly 40 percent using a minimum-headcount exercise built around keeping services running, maintaining regulatory compliance, and rebuilding around artificial intelligence.

How he operates

Dorsey describes Square's and Block's mission with a single word, access, framing the founding insight as a rejection of the financial industry's default posture of distrust in favor of a default of trust verified continuously rather than gated up front.³ He says critical thinking and first-principles problem-solving are skills he tries to improve every day, and he is a vocal Bitcoin advocate. He has said his biggest operating regret at Block was delegating too much, once running it as a holding company with separate chief executives for Square and Cash App, which he says produced mismatched cultures, and that his fix was to recentralize.¹ He also describes deliberately spending credibility with employees, boards, and the public to pursue ideas he believed in, citing Square Capital and Cash App as examples unpopular internally for years before proving out. Dorsey has argued that his 2025 restructuring of Block follows from a broader claim: that organizational hierarchy is an old information-relay mechanism artificial intelligence can now replace. He reorganized the company around three roles: an individual contributor who builds and operates, a directly responsible individual who owns outcomes, and a player-coach who develops others through doing rather than managing as a reporting line. He also describes deliberate discomfort, such as eating one meal a day and cold exposure, as a way of learning what he is capable of.³

Where things stand

As of the mid-2020s, Dorsey remains chief executive of Block, which operates Square, Cash App, and Bitkey as its primary businesses following the 2024 wind-down of TBD, the Tidal scale-back, and the 2025 restructuring. He has no operating role at Twitter or its successor X, having exited the board in 2022 around Musk's acquisition; he has said he no longer believed Musk was the right person to run it. He has also backed decentralized social-networking projects, including early support for Bluesky, which spun out of Twitter during his tenure.² Forbes has estimated his net worth at several billion dollars.

Key facts

• Sent Twitter's first message, "just setting up my twttr," on March 21, 2006, after a two-week hackathon prototype at Odeo.
• Co-founded Square in 2009 with Jim McKelvey; its card reader let anyone plug a smartphone into the headphone jack to take payments. He is the only founder with two companies that have both appeared on the S&P 500.
• Twitter's 2013 IPO raised about 1.8 billion dollars; Square's 2015 IPO priced at 9 dollars a share for a roughly 2.9 billion dollar valuation.
• Square's shift from credit-check gatekeeping to trust-then-verify monitoring raised merchant acceptance rates from roughly 30 to 40 percent to about 99 percent.
• In April 2025 cut Block's workforce by roughly 40 percent and replaced its org chart with three roles: IC, DRI, and Player-Coach.
• At 19, reported a security flaw to a taxi-dispatch firm by emailing from an address made to look like the chairman's, which led directly to a job offer and his move to New York.