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Proprietary software - Wikipedia
Proprietary software | Definition, History, & Facts | Britannica
List of proprietary source-available software - Wikipedia
What Is Proprietary Software? 5 Ways It Beats Open-Source Software - MUO
Proprietary Software - Gartner
List of formerly proprietary software - Wikipedia
Definition of proprietary software | PCMag
List of formerly proprietary software - Wikiwand
What is Proprietary Software? - DevX
What is Proprietary Software? - Definition from Techopedia