Microsoft is opening up its software interfaces for the first time in an attempt to head off criticism from regulators and to capitalise on web-based development trends.
The world's biggest software company will publish more than 30,000 pages of Windows data only available before under very limited licence.
Although it is a major, "disruptive" shift, the commercial reality of Microsoft's dominance remains, according to Janice McGinn research director at analyst The 451 Group.
"Microsoft’s PR machine would have it that it intends to live by the merit of its products, rather than rely on lock-in," she said.
"The reality is its business model is based on dominance - the lock-in mentality and commercial realities have not gone away."
But the world's biggest software company insists that it will drive opportunities across the industry.
"Today's announcement represents a significant expansion toward even greater transparency," said Microsoft chief executive officer Steve Ballmer.
"Our goal is to promote greater interoperability, opportunity and choice for customers and developers throughout the industry by making our products more open and by sharing even more information about our technologies."
