vested interest

vested interest (plural vested interests)

1. (law) an indefeasible right or title, distinguished from a contingent interest, which could be defeated (i.e. cease) if a certain event occurred.
2. a fixed right granted to an employee, especially under a pension plan
3. a stake, often financial, in a particular outcome
4. a group of people or organizations with such a stake
5. an exceptionally strong interest in protecting or promoting something to one's own advantage
   • Oct 24, 2007, Patrick Wintour, The Guardian: Honours investigator calls for change in law

     Mr Yates conceded: "These cases are very difficult to prove because they are bargains made in secret. Both parties have an absolute vested interest in those secrets [not] coming out."

     In this context, "vested" is often used informally for emphasis.

• "Any change is resisted because bureaucrats have a vested interest in the chaos in which they exist." - Richard M. Nixon

• (protecting one's advantage): dog in the hunt, dog in the race, dog in the fight, horse in the race