The Iron Fang Clan were a clan that existed within the Lyran Star Empire.
They were once known as one of the Empire's great clans but sixty years ago, their leader, the Duke Varashar, betrayed his home world by providing information to the "Enemy Whose Name Shall Not Be Spoken Aloud"; the greatest enemy of the Lyran race. This one lone act crippled the clan and nearly cost it all of its ships and status. It's taken two generations for the clan to recover and still they are considered a disgraced group by the rest of the Lyran people.
Any Lyran that joins the Iron Fang Clan does so at the risk of suffering stigma of being considered a pariah. However, the more successful military commanders of the Clan can possibly succeed the Count of the Iron Fang. This can very well change the clan's fortunes and prestige very rapidly depending who comes into power. (TOS video game: Starfleet Command)