Jack Dorsey is the co-founder of Twitter and Block, Inc. (formerly Square). He is one of the most prominent technology billionaires advocating for Bitcoin.
Block (formerly Square)
Dorsey co-founded Square (now Block) in 2009 as a mobile payments company. Under his leadership, Block became one of the first major publicly traded companies to invest in Bitcoin and integrate it into consumer products. Cash App, Block’s consumer payments platform, became one of the most popular ways for retail users in the United States to buy and sell Bitcoin.
In October 2020 and February 2021, Block purchased a total of approximately $220 million in Bitcoin for its corporate treasury. In December 2021, Square officially rebranded to Block, Inc., signaling the company’s deeper commitment to blockchain technology.
Bitcoin Development
Dorsey has directed significant resources toward Bitcoin open-source development. Block created Spiral (formerly Square Crypto), a team dedicated to funding and building open-source Bitcoin projects including the Lightning Development Kit (LDK) and the Bitcoin Development Kit (BDK).
Block also created TBD, a subsidiary focused on building decentralized financial infrastructure, and developed Bitkey, a self-custody Bitcoin hardware wallet designed for mainstream consumers.
Bitcoin Philosophy
Dorsey is a Bitcoin maximalist who has stated that Bitcoin will become the internet’s native currency. He has been critical of other cryptocurrencies and Ethereum, and left the board of Bluesky (the decentralized social network he helped create) over disagreements about its use of non-Bitcoin blockchain technology. He has emphasized Bitcoin’s potential as a tool for financial inclusion in developing countries.
Dorsey co-founded Twitter in 2006 and served as CEO twice — from 2006 to 2008 and again from 2015 to 2021. He stepped down as Twitter CEO in November 2021 to focus on Block.