"We require our external contributors to sign a Contributor License Agreement ("CLA") in order to ensure that our projects remain licensed under Free and Open Source licenses such as MPL2 while allowing HashiCorp to build a sustainable business.
HashiCorp is committed to having a true Free and Open Source Software ("FOSS") license for our non-commercial software. A CLA enables HashiCorp to safely commercialize our products while keeping a standard FOSS license with all the rights that license grants to users: the ability to use the project in their own projects or businesses, to republish modified source, or to completely fork the project."
It's disappointing that the non-legal text on the page repeatedly suggested that signing a CLA would help keep HashiCorp projects open source when the actual text of the license agreement made no such claims.