In the pantheon of tech rivalries, few battles have burned hotter or lasted longer than that between Oracle (ORCL) co-founder Larry Ellison and Microsoft (MSFT). What started as a simple competition for database dominance evolved into an all-out philosophical war — fueled by ambition, ego, and a hunger for total supremacy. Larry Ellison previously said “It’s not enough that we win; all others must lose.”

This quote, often cited as Ellison’s battle cry, perfectly captures the Oracle founder’s cutthroat view of competition — particularly when it came to his long-time nemesis, Bill Gates, and the behemoth he built in Redmond.

Clash of Titans: Oracle vs. Microsoft

Founded in 1977, Oracle quickly became the dominant force in relational databases. Microsoft, meanwhile, was climbing its own mountain with the Windows operating system and, eventually, its SQL Server database.

By the 1990s, Oracle and Microsoft were locked in a brutal competition for control over the database and enterprise software markets. Microsoft’s strategy was straightforward: undercut Oracle’s prices and bundle products to squeeze out competition. Oracle, under Ellison, countered with aggressive innovation and marketing — along with a healthy dose of corporate espionage.

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The “Trashgate” Scandal: Corporate Espionage Unleashed

One of the most infamous episodes in the rivalry was Oracle’s hiring of private investigators in 2000 to dig through Microsoft’s trash — literally.

Oracle was suspicious of Microsoft’s efforts to influence regulatory hearings and public perception by quietly funding think tanks and academic groups. Ellison’s team hired a PR firm to expose the connections. The firm, in turn, hired detectives to sift through the garbage of Microsoft-friendly advocacy groups to uncover a paper trail.

Ellison’s reaction? Pure bravado. He called the investigation a public service, saying “All we did is try to take information that was hidden and bring it to light. I don’t think that was arrogance. I think it was a public service.” 

Ellison further defended the actions on many occasions, including saying “What exactly did we do? What is our corporate espionage? Our corporate espionage is to find out that Microsoft has hired all these companies, these front organizations, and while they pretend to be independent, publishing all sorts of things that are anti-Oracle and pro-Microsoft.” 

While critics accused him of shady tactics, Ellison framed the move as a noble mission to protect the tech industry — and consumers — from Microsoft’s monopolistic ambitions.

Philosophical Divide: Open vs. Closed

At the heart of the rivalry was a deeper ideological divide: Microsoft favored a closed, vertically integrated ecosystem, dominating every level of the software stack. Oracle, while proprietary in its own right, often cast itself as a champion of enterprise freedom — partnering with companies like Sun Microsystems (before acquiring it) and supporting Unix-based systems

The conflict extended into the 2000s and beyond:

• SQL Server vs. Oracle DB: Microsoft’s SQL Server gained ground with smaller businesses, while Oracle retained dominance in high-end enterprise and government.
   
• Azure vs. Oracle Cloud: As the cloud wars took shape, Microsoft surged ahead with Azure, while Oracle struggled to reorient its offerings. Ellison, however, refused to concede defeat—launching bold bets like Oracle Cloud Infrastructure (OCI) and forming surprise partnerships, including one with Microsoft itself in 2019 to enable cross-cloud integrations.

Even as the competitive fire cooled publicly, Ellison remained characteristically combative. “The only way to compete with Microsoft is to never give up. And we don’t.”

Legacy of the Rivalry

Ellison’s war with Microsoft didn’t just shape two companies—it shaped the culture of Silicon Valley. It fueled the rise of enterprise software as a power center, solidified database technology as a battlefield, and demonstrated how far tech leaders would go to win.

Today, both companies are tech titans with revenue in the billions, and a surprising degree of cooperation. But beneath the surface, echoes of that old rivalry still reverberate.