Slack

Market position

Slack is described by the company as a leader in over 303 G2 market reports spanning work management, workflow management, project collaboration, enterprise search, knowledge base, employee Q&A, audio conferencing, business instant messaging and unified workspaces. Historically it competed with Atlassian's HipChat and Stride, which Atlassian shut down effective February 11, 2019, selling the related intellectual property to Slack while taking a minority investment in Slack. Slack was recognized in Credit Suisse's inaugural Disruptive Technology Recognition Program in November 2018. A secondary source characterizes it as the fastest-growing SaaS startup in history and an $16 billion business (0)(5)(7).

Sources emphasize channel-based, conversational collaboration as an alternative to email and meetings; deep integration breadth (teams use an average of 43 apps in Slack, 1.7M apps actively used weekly); external collaboration via Slack Connect; and AI/agent capabilities that operate on the organization's own conversation history and context. Historically, the product's differentiation from IRC included full asynchronicity (messages waiting after logout), easier onboarding and built-in archive search, and it benefited from years of internal dogfooding by the Tiny Speck team before public release (0)(7).

Technology

A cloud collaboration platform combining channel-based messaging, search, file and conversation history, audio/video huddles, and workflow automation, layered with AI: conversation summarization, channel recaps, thread summaries, AI-powered enterprise search, AI meeting notes, and the Slackbot agent that acts across connected apps. The platform is open and extensible via integrations and developer tools, connects to external models and agents (Claude, ChatGPT, GitHub Copilot, Agentforce), and includes a security program described as protecting data at every layer. Native desktop clients are distributed for Windows (64-bit, legacy and ARM 64-bit builds; version 4.51.191 at time of capture) plus Android and iOS apps (0)(1)(2).

Go-to-market

Product-led self-serve sign-up and free downloadable desktop/mobile apps combined with enterprise sales, demos and an enterprise deployment path; a partner channel was announced in November 2019. Marketing leans on customer case studies, third-party analyst-style validation (leader in over 303 G2 market reports), and an app/integration ecosystem that draws in third-party developers. One secondary source notes Slack reached a $1B valuation about eight months after launch without traditional advertising spend or a chief marketing officer (0)(2)(5)(7).

Businesses and teams of all sizes, with an emphasis on enterprise clients — Slack formed a partner channel in November 2019 as part of an enterprise focus, and IBM was reported in February 2020 to be deploying Slack to all 350,000 of its employees, its largest client at that time. Named customer references on the company site include OpenAI, Spotify, ezCater, Signable, Anthropic and Vercel. One secondary source states the product is used by 77% of the Fortune 100 (0)(5)(7).

Geography

Headquartered in San Francisco (Salesforce Tower), California, with offices in New York City, Denver, Toronto, London, Paris, Tokyo, Dublin, Vancouver, Pune and Melbourne; the company serves customers worldwide. The Slack Fund invests across North America and Europe (4)(5).

History

Tiny Speck raised $1.5 million in angel funding in 2009, a $5 million Series A in 2010 from Accel and Andreessen Horowitz, and a $10.7 million Series B in 2011. After Glitch closed in December 2012, the company pivoted to enterprise software, raising $17 million from Andreessen Horowitz, Accel and Social Capital. Slack was developed as a commercial product from 2013, used by roughly 45 companies by May 2013 and released as a "preview release" in August 2013, with desktop, iOS and Android versions by year end. The company renamed itself Slack Technologies in August 2014. Financing continued with $42.75 million (April 2014), $120 million at a $1.2 billion valuation led by Kleiner Perkins and GV (October 2014), a deal to raise up to $160 million at a $2.76 billion valuation (March 2015) and $160 million raised in April 2015, $200 million led by Thrive Capital (April 2016), $250 million largely from the SoftBank Vision Fund (September 2017, bringing total funding to $841 million at a $5.1 billion valuation), and a $427 million Series H at a post-money valuation above $7.1 billion led by Dragoneer Investment Group and General Atlantic. Slack acquired Screenhero in January 2015 and hired its first CFO, Allen Shim, in early 2018. It listed directly on the NYSE under ticker WORK on June 20, 2019, was acquired by Salesforce in a deal announced December 1, 2020 and closed July 21, 2021, and was delisted from the NYSE in June 2021 (3)(5)(6)(7).

Risks & controversies

Slack Technologies reported a net loss of $300 million on $903 million revenue in 2020 and a $138.9 million loss for the fiscal year ending January 2019. Its September 2017 round drew capital largely from the SoftBank Vision Fund, of which about 45% ($112.5 million) originated from Saudi Arabia's Public Investment Fund. Many usage and productivity figures published on the company site are based on Slack internal data and internal surveys rather than independent measurement (0)(5).