Bram Cohen

A 2015 Journal du Net article states that he was born on October 12, 1975, in New York and grew up in Manhattan; his mother teaches and his father is a computer scientist; he has said he learned to program at age five on the family computer. NPR’s 2008 programme says he wrote his first lines of code at age five; on the programme he recalled having a Timex Sinclair computer when he was in the first grade.⁠[1][2]

He recalled that his father taught him BASIC and rudimentary C and that he learned everything else on his own; he also said that he was picked on a lot at school and had trouble making friends, and that his grades suffered because he focused on learning rather than on earning grades.⁠[3]

He attended Stuyvesant High School in New York; the Stuyvesant High School Alumni Association’s page names him “Bram Cohen ’93” (class of 1993). Journal du Net writes that he entered the University at Buffalo in 1993 and abandoned his studies after one year.⁠[1][4]

Journal du Net writes that he adapted poorly to corporate life and changed employers regularly.⁠[1]

He recalled that he had worked at startups for a long time and that the last one ran out of money in early 2001; after that he worked on BitTorrent for quite a long time, living off credit cards.⁠[5]

Journal du Net writes that he left MojoNation in April 2001 and began working on BitTorrent. Accounts of how BitTorrent was written differ: NPR’s 2008 programme says he wrote it at age 26, alone, in a few short weeks; a 2008 Bloomberg Businessweek article says that in his late twenties he spent most of nine months writing the program, sitting on a wooden chair with a Dell keyboard on his lap; an October 2005 Fortune article says he spent two years working on BitTorrent.⁠[1][2][6][7]

On July 2, 2001, he first revealed BitTorrent on a public message board.⁠[8]

Encyclopaedia BritannicaEncyclopædia BritannicaEncyclopædia Britannica is a general English-language encyclopedia first published in Edinburgh, Scotland, in 1768; the name also refers to its publisher, Chicago-based Encyclopædia Britannica, Inc. (which presents itself as The Britannica Group). The print edition ended in 2012, and the company’s main businesses since then have been the online encyclopedia Britannica.com, digital education products for schools and libraries, and Merriam-Webster dictionaries.Open the full entry writes that he created BitTorrent because he was frustrated by the long download times he experienced with applications such as FTP; BitTorrent is a protocol for sharing large computer files over the Internet, in which shared files are divided into smaller pieces distributed among its users, called “peers,” and a tracker keeps records of all the peers that have previously downloaded the file and lets the peer conducting the search download pieces of their copies.⁠[9]

His paper “Incentives Build Robustness in BitTorrent,” dated May 22, 2003, states that BitTorrent uses tit-for-tat as a method of seeking Pareto efficiency and achieves higher robustness and resource utilisation than any cooperative technique then known; each peer always unchokes a fixed number of other peers (four by default), chosen strictly by the current download rate from them, plus a single “optimistic unchoke” peer unchoked regardless of its download rate and rotated every 30 seconds. The paper says BitTorrent routinely served files hundreds of megabytes in size to hundreds of concurrent downloaders, that the largest known deployments had over a thousand simultaneous downloaders, and that the tracker used about a thousandth of the total bandwidth.⁠[10]

In 2004 he teamed up with Ashwin Navin, a former YahooYahooYahoo is an internet brand founded by Jerry Yang and David Filo in 1994, with email, search, news, finance, sports, and advertising businesses. It developed from a web directory into a portal, underwent major acquisitions and security incidents, and sold its operating business in 2017, when the original listed company became Altaba. Apollo-managed funds acquired the brand’s operating business in 2021. Yahoo launched the AI answer service Scout in 2026.Open the full entry executive, to turn the free software into a legitimate business model, founding BitTorrent, Inc. and serving as its first chief executive. “It really took off in early 2003 and we founded the company in 2004,” he said, adding that the company then raised some venture-capital money and that, for delivering large files to many people, BitTorrent “was the only game in town.”⁠[5][11]

In May 2005 he introduced technology that let users search the Internet for torrent files.⁠[12]

In an October 2005 Fortune article Dan Glickman, president of the Motion Picture Association of America, said that the BitTorrent team had some revolutionary ideas and interesting concepts and that the association had been talking with them.⁠[7]

Fortune wrote on October 19, 2005, that the previous month the venture firm DCM-Doll Capital Management (DCM Ventures; the firm was established in 1996 as Doll Capital Management) had invested $8.75 million in BitTorrent.⁠[7][13]

Fortune wrote in October 2005 that BitTorrent, the invention of the 30-year-old Cohen, had attracted over 45 million users and accounted for at least 20% of the entire volume of the Internet; the San Francisco-based company then had 12 people and expected to have 20 by the end of the year.⁠[7]

On November 22, 2005, at a press conference in Los Angeles with MPAA executives, he announced that BitTorrent would remove unauthorized content owned by the MPAA’s members, the seven largest U.S.United StatesThe United States is a federal country in North America made up of 50 states, the District of Columbia as the seat of government, and territories such as Puerto Rico and Guam; its capital is Washington, D.C. The Continental Congress adopted the Declaration of Independence on July 4, 1776. The 2020 census (April 1, 2020) counted a resident population of 331,449,281, and the 435 seats of the House of Representatives are apportioned among the states on the basis of the census.Open the full entry film studios, from the search engine on bittorrent.com; the agreement covered only bittorrent.com and not other search engines with similar functions. “BitTorrent discourages the use of its technology for distributing films without a license to do so,” he said in a statement.⁠[14][12]

In 2007 the BitTorrent Entertainment Network went live, offering content from Warner Bros., Twentieth Century Fox, MTV Networks and others on a download-to-own and download-to-rent basis. He said the target price for download-to-own titles was $9.99 and that the company wanted to limit electronic sell-through until prices would not cause “sticker shock” among its general user base; “a lot of our licenses are U.S. only, unfortunately.” He also said: “The traditional television model is going away as Internet capacity increases.”⁠[5]

In 2008 NPR’s All Things Considered broadcast host Andrea Seabrook’s visit to the 32-year-old at BitTorrent’s headquarters in San Francisco. “I learned how to program at a very young age,” he said on the programme.⁠[2]

BEP 3, “The BitTorrent Protocol Specification” on BitTorrent.org, names him as its author, was created on January 10, 2008, and has the status Final; it defines the tracker interface, the .torrent metainfo file (with the tracker URL, file name, piece length and the SHA1 hash of each piece) and the protocol between peers (after a handshake, length-prefixed messages manage choking, interest, piece availability and requests, with pieces downloaded in random order and checked against their hashes). Other authors added clarifications between 2009 and 2017.⁠[15]

Chia Network’s biography of him states that BitTorrent accounted for 43% to 70% of all Internet traffic in 2009; a 2007 World Screen article says BitTorrent at one point accounted for more than a third of all data sent over the Internet.⁠[11][5]

At BitTorrent he worked as an engineering manager and product manager and served on the board of directors; before leaving he was working, as lead engineer, on a peer-to-peer live video protocol. In August 2017 he left BitTorrent to found Chia Network; Chia Network’s biography says he has been its chairman and chief technology officer since its founding.⁠[11][16][8]

In September 2017 he co-authored the technical paper “Beyond Hellman’s Time-Memory Trade-Offs with Applications to Proofs of Space.”⁠[17]

On November 8, 2017, he announced that Chia Network would launch a cryptocurrency replacing BitcoinBitcoinBitcoin (common symbol BTC) is an open peer-to-peer electronic cash protocol, network, and native digital asset. Full nodes independently verify transactions and blocks according to the consensus rules; transactions are recorded as UTXOs, and blocks are organized into a public ledger through proof of work. Bitcoin is not issued or managed by any single institution, but using, holding in custody, and trading it still involve key, privacy, market, and legal risks.Open the full entry’s energy-intensive verification with proofs of space based on unused hard-drive storage and proofs of time; for the company he had teamed up with Ryan Singer, chief operating officer of the early Bitcoin exchange Tradehill; it had raised a seed round of undisclosed size, which he described as “a very hot round”; early sales were planned for the second quarter of 2018 and a full launch for the end of 2018, which he called a stretch goal.⁠[16]

“The idea is to make a better bitcoin, to fix the centralization problems,” he said, arguing that Bitcoin mining favours those with the cheapest electricity and concentrates influence in a few miners.⁠[16]

In his presentation Chia’s participants are called “farmers” rather than “miners,” and a farmer’s chance of winning a block is proportional to the space allocated relative to the network’s total capacity; Chia planned to implement the Lightning Network after release.⁠[17]

In March 2018 Chia announced a $3.395 million seed round led by AngelListAngelListAngelList is a startup investment platform company based in San Francisco, United States. Founded in 2010 by Naval Ravikant and Babak Nivi, it began as a mailing list recommending startups to angel investors, went on to launch online fundraising, Syndicates (co-investing), rolling funds, and other products, and later shifted into a fund administration and back-office services platform for venture capital funds and private markets.Open the full entry’s Naval RavikantNaval RavikantNaval Ravikant is an entrepreneur and angel investor and a co-founder of AngelList. Early on he co-founded the review site Epinions; he and Babak Nivi later grew AngelList out of the startup-fundraising blog Venture Hacks, and he co-founded the cryptocurrency hedge fund MetaStable Capital and Spearhead, which backs founders to make angel investments. His views on startups and life were compiled into the book The Almanack of Naval Ravikant.Open the full entry, with Andreessen HorowitzAndreessen HorowitzAndreessen Horowitz (a16z) is a venture capital firm founded in 2009 by Marc Andreessen and Ben Horowitz. It invests from the seed stage through the growth stage and provides operational support to its portfolio companies.Open the full entry, Greylock, True Ventures, Ravikant’s crypto hedge fund MetaStableMetaStable CapitalMetaStable Capital is a cryptocurrency investment fund co-founded in 2014 by Naval Ravikant, Lucas Ryan and Josh Seims. Historically based in San Francisco, it pursued long-term holdings and investments in blockchain networks and infrastructure. Dragonfly announced its acquisition of the fund in August 2022.Open the full entry, Danhua Capital and DCM taking part; DCM was also BitTorrent’s leading shareholder. TechCrunchTechCrunchTechCrunch is an American technology news outlet founded in 2005 by Michael Arrington and Keith Teare and headquartered in San Francisco; it mainly covers technology companies, startups, and venture capital, and hosts events such as TechCrunch Disrupt. Its ownership passed successively through AOL, Verizon, and Yahoo, and in 2025 Regent announced its acquisition.Open the full entry wrote that this time he was keeping control by holding the chief executive title himself.⁠[18][19]

Chia was then planning a “mini-IPO” that summer or fall under the JOBS Act’s Regulation A+ rule, which could raise up to $50 million from the public, non-accredited investors included, through an auction in which investors choose how much to bid for how many shares, similar to the process GoogleGoogleGoogle is an American technology company founded by Larry Page and Sergey Brin and incorporated in 1998. It became an Alphabet subsidiary in 2015. Its businesses include internet search, advertising, software platforms, cloud computing, and artificial intelligence.Open the full entry used for its IPO; Chia planned to pre-mine its currency while initially retaining all of the coins, to issue a dividend of Chia to its shareholders before the network launch, and to launch its coin and blockchain in the first quarter of 2019.⁠[18][19]

“You absolutely must worry on a technical level about all the ways something could go wrong because building secure distributed databases is hard,” he said. Asked whether Chia had a white paper, he laughed: “We have actual papers in refereed journals.”⁠[18]

In July 2018 TRON, a San Francisco–based blockchain platform, acquired BitTorrent.⁠[9]

Documents obtained by CoinDeskCoinDeskCoinDesk is a cryptocurrency media, events, index, and data company founded in 2013 and headquartered in New York. Its businesses include the CoinDesk news website, the annual crypto industry conference Consensus, and the CoinDesk Indices index business. In November 2023, the digital asset exchange Bullish acquired CoinDesk from Digital Currency Group, and CoinDesk has since operated as an independent subsidiary of Bullish.Open the full entry show that TRON founder Justin SunJustin SunJustin Sun is the founder of the blockchain platform TRON. In 2018 he and TRON acquired the file-sharing company BitTorrent, and from December 2021 to March 2023 he was Grenada’s ambassador to the World Trade Organization.Open the full entry submitted his winning acquisition offer to the BitTorrent board on February 14, at a sale price of $119 million, of which common stockholders received $29,343,986; at the time of the acquisition he still owned 31% of BitTorrent’s common stock, though CoinDesk writes that his attention was by then primarily directed at the new venture. The next day the BitTorrent board unanimously approved an agreement with him granting a “full release” of some of its intellectual property in exchange for the right to invest $50,000 in Chia through a SAFE (simple agreement for future equity); the two sides also agreed on mutual releases and non-disparagement. CoinDesk wrote in 2019 that the deal required him, as a major shareholder, to play an active part.⁠[19][20]

TechCrunch in November 2017 and CoinDesk in August 2018 both wrote that he remained on BitTorrent’s board after leaving to start Chia; CoinDesk writes that he left to start Chia in late 2017. On August 19, 2018, TorrentFreak published his answer, “I have no involvement with Tron,” and noted that mail to his BitTorrent address returned an automatic reply suggesting he no longer used it.⁠[16][19][8]

In June 2019 he became chief executive of Chia Network; co-founder Ryan Singer stepped away to focus on family priorities, and chief financial officer and general counsel Mitch Edwards took over existing business-development relationships. Chia describes its cryptocurrency as “enterprise-grade”; from the previous October Chia had run optimisation contests with its community and open-sourced the best implementations, with a second contest beginning in April 2019. TechCrunch’s March 2018 article had already described him as holding the chief executive title at Chia.⁠[20][11][18]

Chia Network’s release states that under his leadership Chia Network created the Chialisp development language and launched the Chia blockchain mainnet in March 2021.⁠[21]

In May 2021 Chia Network raised $61 million from investors including Richmond Global Ventures and Andreessen Horowitz, with Breyer Capital, Slow Ventures, True Ventures, Cygni Capital, Naval Ravikant, Collab+Currency and DHVC also taking part; a person familiar with the matter put the company’s valuation in the round at about $500 million, more than double its previous valuation. Gene Hoffman, then president and chief operating officer, said the company was looking at a traditional IPO as soon as that year, though a merger with the “right” special purpose acquisition company was possible: “Our goal has always been to go public relatively quickly.”⁠[22]

From January 1, 2023, Gene Hoffman, previously chief operating officer, took over as president and chief executive of Chia Network, and, in the release’s words, he moved from chief executive to chairman of the board, founder and chief technology officer; the company said the change would scale its organisation and support its goal of going public. “I built Chia because I knew blockchain could be better,” he said in the January 19 release, adding that “Gene shares my vision for a future with more secure and sustainable financial technology.”⁠[21][23]

On April 13, 2023, Chia Network announced that it had confidentially submitted a draft registration statement on Form S-1 for a proposed initial public offering to the U.S. Securities and Exchange CommissionU.S. Securities and Exchange CommissionThe U.S. Securities and Exchange Commission is the federal securities regulator of the United States. Created during the Great Depression by the Securities Exchange Act of 1934 and led by five commissioners, it has a three-part mission of protecting investors, maintaining fair, orderly and efficient markets, and facilitating capital formation.Open the full entry, with the size and price range not yet determined; the photo caption in BloombergBloomberg L.P.Bloomberg L.P. is a global financial technology, data and media company founded by Michael Bloomberg in 1981. It began by providing terminal services that deliver data, analytics and news to financial professionals, and launched Bloomberg News in 1990. Michael Bloomberg has pledged the vast majority of the company’s profits to his philanthropic organization, Bloomberg Philanthropies.Open the full entry’s report on it names him as Chia Network’s chairman and founder. On August 12, 2024, Chia announced that it had confidentially submitted an amendment to its initial draft registration statement, its third confidential submission.⁠[24][25][26]

As of November 2026, Chia Network’s profile page lists his titles as chairman of the board, founder and chief technology officer (the biography text on the same page still says he has been chief executive since June 2019). His GitHub profile reads “The big kahuna at Chia. Formerly created BitTorrent.” and gives his location as San Francisco.⁠[11][27]

In a 2005 interview he said he met his wife through someone he worked with and declined to go into more detail. A 2015 Journal du Net article states that he lived in San Francisco with his wife, Jenna, and their three children.⁠[3][1]

He has said he will not take jobs with strict hours or dress codes: “I won’t work anywhere which requires me to work strict hours or follow a dress code.”⁠[3]

He has said publicly that he has Asperger’s syndrome. Journal du Net writes that he self-diagnosed the syndrome; in a 2005 interview with Wrong Planet he said: “I never really identified as having it until I started to learn some basic social signaling.” He also said he was unsure whether his aversion to strict hours and dress codes was related to it.⁠[1][3]

In 2008 he said on NPR that he sometimes needs friends to remind him what is socially appropriate; friends had said it felt weird to talk to him, so he taught himself to look people in the eye during conversations: “I’m good enough at it now that I can mostly function reasonably.”⁠[2]

Chia Network’s biography of him calls him one of the top-selling puzzle designers in the world.⁠[11]

He briefly worked on ValveValveValve is a video game company based in Washington State, United States. Founded in 1996 by Gabe Newell and Mike Harrington, it developed games including Half-Life and operates the PC game distribution platform Steam.Open the full entry’s Steam.⁠[16]

Popular repositories under his GitHub account include manyana; DissidentX, described as “Bram’s steganographic framework”; MerkleSet, a highly performant Merkle set data structure; Weave, a reference implementation of a weave data structure for quickly rebuilding older versions of compressed version-controlled repositories; UtahDataCenter, “A tool for logging everything”; and prescad, “Openscad without the spaghetti.”⁠[27]

Chia Network’s biography of him states that he is often accused of being Satoshi NakamotoSatoshi NakamotoSatoshi Nakamoto is the pseudonymous creator of Bitcoin, who published the Bitcoin white paper in 2008, released the first Bitcoin software and launched the blockchain in 2009, and stopped public activity around 2011; the person’s true identity has never been confirmed.Open the full entry, a claim he denies.⁠[11]

Chia Network: Official website: https://www.chia.net/ (opens in a new window).⁠[11]

X: Public account: https://x.com/bramcohen (opens in a new window).⁠[11]

LinkedInLinkedInLinkedIn is a social networking platform for professionals. It was founded in 2002 by Reid Hoffman and others, launched in 2003, and listed on the New York Stock Exchange in 2011; after Microsoft acquired it for approximately $26.2 billion in 2016, it became a wholly owned Microsoft subsidiary. Its revenue comes from membership subscriptions, advertising, and recruitment solutions.Open the full entry: Public profile: https://www.linkedin.com/in/cohenbram/ (opens in a new window).⁠[11]

GitHub: Public account: https://github.com/bramcohen (opens in a new window).⁠[27]