Discipline: Economics
Co-operation between two or more companies producing similar goods may entail similar pricing or output levels.
These conditions of competition may be more akin to a monopoly market.
Collusion is outlawed in most capitalist economies.
Also see: administered pricing, monopolistic competition, monopoly, monopoly capitalism
Source:
G J Stigler, 'A Theory of Oligopoly', Journal of Political Economy, 72, 1 (February, 1964), 44-61