Few rivalries in the technology sector have shaped markets or generated as much pointed rhetoric as the ongoing tension between Salesforce and Microsoft. In the current landscape, where artificial intelligence, cloud delivery, and collaboration tools define the competitive edge for enterprise software giants, fresh allegations from Salesforce CEO Marc Benioff have reignited debates on fairness, strategy, and the future of open digital ecosystems. Benioff’s latest salvo—accusing Microsoft of deploying “horrible” and “dark” tactics against Slack prior to its acquisition, and warning that a similar playbook may be unfolding with OpenAI—has implications far beyond the bounds of Silicon Valley boardrooms.
To understand Benioff’s claims, it's crucial to revisit the formative clashes that set the stage for today’s enterprise software landscape. In 2020, Salesforce landed a $27 billion deal to acquire Slack, the workplace messaging platform often hailed as the spiritual successor to email for modern teams. The purchase came four years after Microsoft reportedly balked at an $8 billion price tag for Slack, opting instead to double down on Skype and fast-track the creation of Microsoft Teams—the company's own answer to the growing appetite for integrated communications tools.
This decision would pivot Microsoft into direct competition with Slack, quickly escalating into one of the most visible feuds in recent tech history. Slack accused Microsoft of anti-competitive behavior, focusing attention on Microsoft's bundling of Teams with its productivity behemoth, Office 365 (now Microsoft 365). In a complaint filed with the European Commission in 2020, Slack alleged that Microsoft was “illegally” abusing its market power, effectively forcing Office customers into adopting Teams—whether they wanted it or not.
This bundling, Slack argued, not only stifled competition but echoed the same tactics Microsoft was accused of using in the infamous browser wars of the late 1990s, where Internet Explorer was tightly woven into the Windows operating system, resulting in protracted antitrust litigation. According to Benioff, “You can see the horrible things that Microsoft did to Slack before we bought it. That was pretty bad and they were running their playbook and did a lot of dark stuff. And it's all gotten written up in an EU complaint that Slack made before we bought them.”
In response to mounting regulatory pressure, Microsoft in late 2023 agreed to unbundle Teams from Microsoft 365 and Office 365 in Europe, a move widely interpreted as a concession to antitrust concerns. Financial disclosure documents confirm that while Microsoft defended its bundling strategy as pro-customer, it ultimately chose to cooperate with European authorities, indicating that these anti-competitive allegations were not without merit.
Benioff argues that a comparably aggressive “playbook” is being executed today, with Microsoft’s business DNA still shaped by a desire to “own it all, control it all”—as he claimed in his podcast interview with SaaStr CEO Jason Lemkin. Critics suggest that Microsoft’s repeated moves—rapidly building or acquiring rivals to hot startups, integrating them deeply into dominant platforms, and leveraging proprietary APIs or exclusive features—constitute a cycle that threatens open competition.
While Microsoft rarely comments directly on such accusations, its strategy of integrating Teams with Office 365 (and, more recently, embedding AI assistant Copilot into every facet of Microsoft 365 and Windows) echoes these patterns. The intent is clear: by weaving new tools into the productivity workflow, Microsoft can create stickiness and fend off competitors before they become existential threats.
Microsoft's investment in OpenAI has been extensive. Beginning in 2019, Microsoft invested billions, culminating in ownership of a significant minority stake by early 2023, and a right of first refusal on any full acquisition of the AI lab. OpenAI’s GPT models—including ChatGPT and the engine behind Microsoft Copilot—became central to Microsoft’s next generation of search, productivity, and developer tools.
Initially, the partnership was publicly lauded: OpenAI CEO Sam Altman himself dubbed it “the best bromance in tech.” Microsoft repeatedly described OpenAI’s frontier models as the core of its generative AI strategy. But by late 2023 and early 2024, cracks in the partnership began to show:
Some analysts argue that while bundling and tight integration are legitimate business strategies, the risk arises when a dominant player leverages monopoly power in one market to forcibly expand into another—thus limiting consumer choice and raising barriers to entry. EU and US regulators have both signaled a renewed appetite for investigating large tech companies, and Microsoft’s past behavior makes it a perennial subject of scrutiny.
Industry observers point out that Microsoft's shift from acquisition to strategic partnership—especially in the AI space, where direct competition with the likes of Google, Amazon, and Meta is fierce—may be necessary for survival. But the line between partnership and “embrace, extend, extinguish,” as Microsoft’s critics have long described it, remains blurry, requiring continual vigilance from both competitors and regulators.
2. Scale and Reach: With a ubiquitous global footprint, Microsoft can deploy new features at a scale few can rival. This accelerates the adoption of innovations—sometimes driving standards in areas like security, compliance, and data integration.
3. Speed of Innovation: By leveraging its Azure cloud backbone, Microsoft can bring new AI capabilities to market rapidly—whether through internal R&D, partnerships like OpenAI, or integration with existing products.
2. Stifled Competition and Innovation: When dominant platforms integrate or mimic competitors’ features, smaller innovators may struggle to gain traction, potentially starving the ecosystem of disruptive ideas. This risk is heightened in fields like AI, where access to proprietary training data and cloud-based compute power consolidates control among top players.
3. Erosion of Trust in Partnerships: If Microsoft’s approach to partnerships is viewed as opportunistic or predatory—“feigning acquisition, then pivoting to competition”—potential partners may become more guarded, slowing the collaborative pace of innovation that underpins much of the tech sector's progress.
Regulators in both Europe and the United States are closely monitoring developments in bundling, platform dominance, and strategic partnerships—particularly as similar issues surface around Amazon Web Services, Google Cloud, and collaboration companies like Zoom or Slack. The industry’s willingness to adopt open standards, ensure interoperability, and provide meaningful choices to customers will determine not only compliance but also customer trust.
For its part, Microsoft has demonstrated adaptability: agreeing to unbundle Teams in European markets, responding to regulatory inquiries, and providing some transparency around its AI collaborations. Yet the fundamental tension—between turning partnership into dominance and allowing true multi-vendor ecosystems to flourish—remains unresolved.
The evolving drama between Salesforce, Slack, Microsoft, and OpenAI encapsulates a broader truth: that in technology, today's partners are often tomorrow's rivals, and yesterday’s tactics may not—indeed, should not—define the digital world of tomorrow. Only by scrutinizing these dynamics openly, learning the hard lessons of past battles, and insisting on robust competition, can the industry ensure that innovation benefits users, not just corporate giants.
The Battlefield: Slack, Teams, and the Art of the Corporate War
To understand Benioff’s claims, it's crucial to revisit the formative clashes that set the stage for today’s enterprise software landscape. In 2020, Salesforce landed a $27 billion deal to acquire Slack, the workplace messaging platform often hailed as the spiritual successor to email for modern teams. The purchase came four years after Microsoft reportedly balked at an $8 billion price tag for Slack, opting instead to double down on Skype and fast-track the creation of Microsoft Teams—the company's own answer to the growing appetite for integrated communications tools.This decision would pivot Microsoft into direct competition with Slack, quickly escalating into one of the most visible feuds in recent tech history. Slack accused Microsoft of anti-competitive behavior, focusing attention on Microsoft's bundling of Teams with its productivity behemoth, Office 365 (now Microsoft 365). In a complaint filed with the European Commission in 2020, Slack alleged that Microsoft was “illegally” abusing its market power, effectively forcing Office customers into adopting Teams—whether they wanted it or not.
This bundling, Slack argued, not only stifled competition but echoed the same tactics Microsoft was accused of using in the infamous browser wars of the late 1990s, where Internet Explorer was tightly woven into the Windows operating system, resulting in protracted antitrust litigation. According to Benioff, “You can see the horrible things that Microsoft did to Slack before we bought it. That was pretty bad and they were running their playbook and did a lot of dark stuff. And it's all gotten written up in an EU complaint that Slack made before we bought them.”
Verifying the Claims: Analysis and Fact-Checking
Benioff’s criticisms are substantiated by multiple independent reports and regulatory filings. Slack’s EU complaint (available from the European Commission’s public records) specifically accused Microsoft of tying Teams to its dominant suite of productivity software and “refusing to provide critical interoperability information.” Press coverage by The Verge, The Wall Street Journal, and the BBC all corroborate that regulators in the EU subsequently opened an inquiry into Microsoft’s practices—an ongoing process as of early 2024.In response to mounting regulatory pressure, Microsoft in late 2023 agreed to unbundle Teams from Microsoft 365 and Office 365 in Europe, a move widely interpreted as a concession to antitrust concerns. Financial disclosure documents confirm that while Microsoft defended its bundling strategy as pro-customer, it ultimately chose to cooperate with European authorities, indicating that these anti-competitive allegations were not without merit.
The “Playbook”: Historical Parallels and Persistent Criticism
To contextualize Benioff’s rhetoric, it is vital to examine Microsoft’s historical “playbook”—from the Netscape saga to more recent competitors. In the 1990s, Microsoft’s bundling of Internet Explorer with Windows led to a landmark antitrust trial, with a US court eventually ruling that Microsoft had violated antitrust laws by using its operating system monopoly to undercut competition. Microsoft’s legal troubles in the EU persisted well into the next decade, with multi-billion-dollar fines levied for similar bundling strategies concerning Windows Media Player and other software.Benioff argues that a comparably aggressive “playbook” is being executed today, with Microsoft’s business DNA still shaped by a desire to “own it all, control it all”—as he claimed in his podcast interview with SaaStr CEO Jason Lemkin. Critics suggest that Microsoft’s repeated moves—rapidly building or acquiring rivals to hot startups, integrating them deeply into dominant platforms, and leveraging proprietary APIs or exclusive features—constitute a cycle that threatens open competition.
While Microsoft rarely comments directly on such accusations, its strategy of integrating Teams with Office 365 (and, more recently, embedding AI assistant Copilot into every facet of Microsoft 365 and Windows) echoes these patterns. The intent is clear: by weaving new tools into the productivity workflow, Microsoft can create stickiness and fend off competitors before they become existential threats.
The OpenAI Chapter: A “Partnership” in Flux
Benioff’s warnings, however, do not rest solely on the legacy of the Slack-Microsoft saga. He sees history repeating—or at least rhyming—in Microsoft’s fast-evolving relationship with OpenAI.Microsoft's investment in OpenAI has been extensive. Beginning in 2019, Microsoft invested billions, culminating in ownership of a significant minority stake by early 2023, and a right of first refusal on any full acquisition of the AI lab. OpenAI’s GPT models—including ChatGPT and the engine behind Microsoft Copilot—became central to Microsoft’s next generation of search, productivity, and developer tools.
Initially, the partnership was publicly lauded: OpenAI CEO Sam Altman himself dubbed it “the best bromance in tech.” Microsoft repeatedly described OpenAI’s frontier models as the core of its generative AI strategy. But by late 2023 and early 2024, cracks in the partnership began to show:
- OpenAI’s Stack Announcement: In spring 2024, OpenAI revealed technical details of its next-generation stack—surprisingly, making no mention of Microsoft, despite the latter running a significant GPU cluster for OpenAI on Azure.
- Microsoft’s Alternative Models: Multiple reports, as covered by Reuters and the Financial Times, indicate that Microsoft had explored developing and deploying alternative internal and third-party AI models for its own Copilot services, suggesting a hedged approach.
- Changes to Exclusivity Terms: The exclusivity arrangement between Microsoft and OpenAI was quietly revised, reportedly carving out exceptions and reducing Microsoft’s lock-in power, although the company maintained a right of first refusal on future OpenAI sales or mergers.
Is This Merely Aggressiveness, Or Something More?
Enterprise software has always been defined by aggressive competition. As SaaStr CEO Jason Lemkin acknowledged in his podcast exchange with Benioff, there is an “inherent aggressiveness in enterprise software.” But there is a fine line between assertive market play and actions that trigger antitrust concerns or stifle innovation.Some analysts argue that while bundling and tight integration are legitimate business strategies, the risk arises when a dominant player leverages monopoly power in one market to forcibly expand into another—thus limiting consumer choice and raising barriers to entry. EU and US regulators have both signaled a renewed appetite for investigating large tech companies, and Microsoft’s past behavior makes it a perennial subject of scrutiny.
Industry observers point out that Microsoft's shift from acquisition to strategic partnership—especially in the AI space, where direct competition with the likes of Google, Amazon, and Meta is fierce—may be necessary for survival. But the line between partnership and “embrace, extend, extinguish,” as Microsoft’s critics have long described it, remains blurry, requiring continual vigilance from both competitors and regulators.
Weighing the Evidence: Strengths, Risks, and Industry Implications
Notable Strengths
1. Integrated User Experience: Microsoft’s strategy of bundling new products like Teams and Copilot into Office 365 has significantly enhanced workflow integration for millions of users. Unified logins, cross-app features, and seamless updates reduce friction for enterprise IT teams and end users alike.2. Scale and Reach: With a ubiquitous global footprint, Microsoft can deploy new features at a scale few can rival. This accelerates the adoption of innovations—sometimes driving standards in areas like security, compliance, and data integration.
3. Speed of Innovation: By leveraging its Azure cloud backbone, Microsoft can bring new AI capabilities to market rapidly—whether through internal R&D, partnerships like OpenAI, or integration with existing products.
Potential Risks
1. Antitrust Exposure: As Benioff’s statements—and ongoing regulatory proceedings—highlight, Microsoft’s aggressive bundling practices could invite more than just reputational harm. Regulatory enforcement in the EU, US, and other jurisdictions could result in hefty fines, forced unbundlings, or constraints on future product design.2. Stifled Competition and Innovation: When dominant platforms integrate or mimic competitors’ features, smaller innovators may struggle to gain traction, potentially starving the ecosystem of disruptive ideas. This risk is heightened in fields like AI, where access to proprietary training data and cloud-based compute power consolidates control among top players.
3. Erosion of Trust in Partnerships: If Microsoft’s approach to partnerships is viewed as opportunistic or predatory—“feigning acquisition, then pivoting to competition”—potential partners may become more guarded, slowing the collaborative pace of innovation that underpins much of the tech sector's progress.
The Path Forward: Regulatory, Competitive, and Strategic Considerations
Benioff’s call to “rip up” the old Microsoft playbook is both a critique and a challenge, reflecting a broader industry reckoning with power, platformization, and the role of antitrust enforcement in safeguarding digital markets. As artificial intelligence, cloud computing, and productivity software become inseparable from daily business operations, the stakes for competitive fairness and user choice will only rise.Regulators in both Europe and the United States are closely monitoring developments in bundling, platform dominance, and strategic partnerships—particularly as similar issues surface around Amazon Web Services, Google Cloud, and collaboration companies like Zoom or Slack. The industry’s willingness to adopt open standards, ensure interoperability, and provide meaningful choices to customers will determine not only compliance but also customer trust.
For its part, Microsoft has demonstrated adaptability: agreeing to unbundle Teams in European markets, responding to regulatory inquiries, and providing some transparency around its AI collaborations. Yet the fundamental tension—between turning partnership into dominance and allowing true multi-vendor ecosystems to flourish—remains unresolved.
Conclusion: An Ongoing Saga
Marc Benioff's recent statements are more than corporate sparring; they serve as a lens into how ecosystem power, regulatory frameworks, and the very definition of innovation are being contested in real time. With the stakes surrounding AI, cloud, and productivity software only set to grow, the need for verifiable claims, transparent business practices, and vigilant regulatory oversight has never been higher.The evolving drama between Salesforce, Slack, Microsoft, and OpenAI encapsulates a broader truth: that in technology, today's partners are often tomorrow's rivals, and yesterday’s tactics may not—indeed, should not—define the digital world of tomorrow. Only by scrutinizing these dynamics openly, learning the hard lessons of past battles, and insisting on robust competition, can the industry ensure that innovation benefits users, not just corporate giants.
