Board of directors hires a CEO. Gives them funding and requires they produce a return. CEO hires upper management. Gives them funding, requires return. Upper management hires middle management. Funding, demands return. Etc...

This is a hierarchy of oaths. It's just not as ceremonial as you've put it. It's also not directly agrarian (and territorial) as you'd expect from a medieval feudalist regime, but the basic structure is still present.