SYDLE Seed - SYDLE BPM is a 100% web BPMS that provides agility in construction and ease in managing your processes. Try it for FREE!
Camunda - The Universal Process Orchestrator
Bizagi - Bizagi is a Business Process Management (BPMS) solution for faster and flexible process automation. It's powerful yet intuitive BPM Suite is designed to make your business more agile.
jBPM - jBPM is a flexible Business Process Management (BPM) Suite.
ProcessMaker - ProcessMaker is an easy to use BPM and workflow software solution. It is used to design, automate, and deploy business processes of any kind.
Imixs-Workflow - Imixs Workflow is a BPM Framework with the goal to reduce the complexity of business applications.