Statamic has been sold since 2012. Its cofounders, Jack McDade and Mubashar Iqbal, built the first flat-file version. Version 3 became a Composer package for Laravel apps, and Statamic 6 is the current major version. Content is stored as Markdown files with YAML data by default, so it can be versioned in Git. Data repositories let content live in a database instead.
Statamic is open core. The vendor calls Core free and open source. Pro and Enterprise are commercial software under a proprietary licence that allows one production site per licence and no redistribution. The licence type of Core is not stated on the pages we read. Editors use a control panel with blueprints, 40+ fieldtypes, the Bard block editor and Live Preview. The API, multi-site and multi-user features need Pro.