Clang has its own limitations. And it takes more effort than just writing the checkers. We open sourced our previously proprietary static analyzer (mostly base

Clang has its own limitations. And it takes more effort than just writing the checkers. We open sourced our previously proprietary static analyzer (mostly based on Clang but also integrated other useful tools) but the commercial/enterprise edition still has its own value in stability, quality assurance, and technical support. It's more like building a Linux distro (e.g. RHEL) from various FOSS components.