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person1995–present

Mark Leonard

Disciplines:
software
capital allocation
software/vertical software
enterprise software/constellation software

Summary

Canadian entrepreneur who founded Constellation Software in 1995 — and built it into a $40B+ company by acquiring vertical market software companies and never selling them — becoming one of the greatest capital allocators in history through a simple, consistent strategy.

Core Contribution

Built the most successful software holding company in history through a single insight: acquire vertical market software companies that dominate niche markets, never sell them, and let them compound — the Constellation CSI model of permanent ownership at fair prices out-competes PE's buy-and-flip model.

Key Spikes & Highlights

  • Never Sell (Constellation Software's foundational rule: unlike PE which buys and sells, Constellation acquires vertical software companies permanently — the permanent ownership creates different incentives, different time horizons, and different relationships with management that lead to better outcomes than short-term ownership)

Historical Influences

Warren Buffett Thorndike's The Outsiders

Intellectual Lineage

University of Western OntarioVentures WestConstellation Software

Contemporaries & Peers

Warren Buffett Henry Singleton

Minds Influenced

Vertical software acquisition industry Capital allocation philosophy Founders podcast content

Intellectual Posterity

Constellation Software CSI shareholder lettersVertical software acquisition model Mark Leonard as greatest capital allocator in history

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