Once Hipmunk sold itself to SAP Concur, it was SAP's IP. SAP could do whatever they wanted with it including burning it down to the ground. And that is what they did rather than selling it back to the founders.
Sad fact of life, yes.
Fascinating. How the employees banded together, etc.
Apparently, more former and current employees are getting involved although I think as far as SAP is concerned, this is trivial and case closed.