The Market Consortium was a civilian authority within the Confederacy of the Worlds of the First Quadrant. They held considerable amount of influence within the Confederacy to the point that the government never enters a trade agreement without the Consortium's supervision.
Since then, the organization became a system that was controlled by individuals who are personally enriched by the regulations they impose.
They hold a monopoly over many technologies within the backward Delta Quadrant power, to the point that they have stagnated its technological development. For example, the Consortium has held a material ownership decree for technology that is very similar to replicators for forty years without developing that technology.
In 2382, when the Federation and Confederacy began initial negotiations, the Consortium stole plans for the universal translator from Harry Kim's combadge. Later on, First Consul Lant Dreeg made a list of demands from Admiral Kathryn Janeway to acquire several pieces of the Federation's advanced technology such as bio-neural circuitry, slipstream drive, and holodeck, in exchange for an alliance. Knowledge on such technology was illicitly acquired from the spies of the Consortium. The Consortium's greed combined with the Confederacy's self-serving philosophy was a number of factors that led the Federation to realize a alliance with the Confederacy was near to impossible.
Unfettered, the Consortium made a backdoor deal with the Kinara to give Admiral Janeway to them. Doing so the Consortium could force the Presider of the Confederacy to extort the technologies of the Federation in exchange for their military assistance in retrieving the admiral. (VOY novel: Acts of Contrition)