The Gray Syndicate is a politically neutral conglomerate of shady enterprises, ranging from smuggling to piracy. They are run by an individual based on Tomin Kora known only as Mister Gray.
Business brings money. Friendship doesn't.
The Gray Syndicate doesn't have an official charter, although it does follow certain guidelines - known as the Gray Code. The code governs command structures aboard pirate/smuggler vessels, distribution of loot, and conflict resolution.
The structure of the Gray Syndicate is hierarchal and based on 'franchise' style agreements. Smaller organizations pay tribute to superiors, and in theory the money eventually makes it to the top of the tree. This structure has made the Gray Syndicate quite durable over a period of time, as many small groups that are caught, killed, or otherwise ended by law enforcement and rivals are irrelevant to the continued operation of the Syndicate as a whole.
The Gray Syndicate operates in the open on the worlds they are heavily affiliated with. In some cases, such as G'ahnlo and Antimone, the local culture generally does not mind the activities of the syndicate, so long as they are not disruptive. This makes these places havens for smugglers, traffickers, and non-violent Syndicate work.
Other areas, such as the Ungstiri Asteroid Belt, the locals simply do not have the ability to oppose the Syndicate, and tend to allow them to operate. Once again, so long as they do not push the locals too hard, lest they start considering the possibility of retribution.
The Gray Syndicate has a few rivals. The first of these are independents. Those involved in operations the Gray Syndicate demands tribute for that simply do not pay end up in this group. Most of these do not last terribly long, as they are hunted by both the Syndicate and law enforcement agencies through the Orion Arm and beyond.
Local groups, mostly on the planetary level, or the next threat to Syndicate operations. Most of these groups have either cultural support within their base of operations, or simply have superior infrastructure. Even then, most are willing to work with the Syndicate and allow them to take over operations beyond their area, if only due to the fact the local groups are unable to compete with the Syndicate on a wide scale.
Niche marketers are a third category. These groups are similar to local groups in that they tend to have a superior infrastructure within a small field and/or area. Once again, these groups tend to work with the Syndicate if operations expand beyond their narrow expertise.
Finally, there are law enforcement agencies and some military forces that work against the Syndicate and their operations. Often, in areas where the Syndicate is opposed by law enforcement front businesses and subterfuge are favored over open operation.