Obadiah Stane was a ruthless manipulator who studies adversaries to find weaknesses to exploit. Stane enjoyed chess, and lived his life with methodical logic. In addition, he was a strong believer in using psychological manipulation to his advantage. For example, in a childhood chess match against another boy whose skill at least equaled his own, he killed the boy's dog so that the other would be distracted from the game. His father, Zebediah, was a degenerate gambler who considered himself on a "lucky streak". As a child, Obadiah saw his father shoot himself in the head while playing a game of Russian roulette. This trauma shaped Obadiah Stane for years to come.
In adulthood, as a wealthy financier, Obadiah Stane became the president and CEO of his own company, Stane International, as a munitions dealer. He also goes into business with Howard Stark. When Stark and his wife die in a car accident, Stane turns his sights on acquiring control of Stark International, the industrial corporation he had worked with, owned by Stark's son, Tony. Stane has his agents, the Chessmen, attacked Stark Industries and assaulted Stark's confidant, James Rhodes. He also confronted Tony Stark in person. Stane also sets up Indries Moomji as Stark's lover without Stark knowing that Moomji was actually the Chessmen's Queen. Meanwhile, Stane and his associates conspires to lock Stark International out of various business deals. Stark eventually learns that Stane is the mastermind behind these attacks, but was unable to confront him. The assaults on Stark, his business, and his friend push Stark to the edge, and he catastrophically relapsed into alcoholism. With the help of S.H.I.E.L.D., Stane buys out Stark International, which he then renames Stane International. Stark, having fallen off the wagon, relinquishes his armor to Jim Rhodes and disappears to be a homeless vagrant. Rhodes becomes the new Iron Man while ignoring Stane's demands to relinquish the armor. Rhodes, as the new Iron Man, eventually thwarts Stane in his attempt to take over the Iron Man battle-suits. Stane proceeds in manufacturing and supplying munitions and weapons to S.H.I.E.L.D. and others who could pay for them. When Tony Stark left, he left behind notes and information on the Iron Man armor. These notes are incomplete and hard to analyze, but Stane assigns a team of scientists to decipher them; they eventually create the Iron Monger armor which, according to Stane, is "far superior to Stark's Iron Man armor". He even considered selling them to the highest bidder or creating an army of Iron Mongers, using them to "take over any country he wanted". Stane assigns the Termite to sabotage another business rival. He also forms an alliance with Madame Masque.
While living on the streets, Stark befriends a pregnant homeless woman. She dies in childbirth, whereupon Stark promises to protect the child. This vow helps Stark overcome his alcoholism. When Stark recovers, he builds a new suit of Iron Man armor, creating the pinnacle of armor design, the Silver Centurion armor; he also founds a new, successful computer company, Circuits Maximus. Stane orders the abduction of Bethany Cabe, and is revealed as Madame Masque's lover. He sends the Circuits Breaker to attack Circuits Maximus, and realizes that the "new" Iron Man is in fact Tony Stark. Upon learning of his rival's recovery, Stane decides to kill him off once and for all. Stane exchanges the minds of Madame Masque and Bethany Cabe, has Happy Hogan, Pepper Potts, and Bambi Arbogast kidnapped, and then kills Morley Erwin by blowing up Circuits Maximus. Stane believes that these losses would drive Stark back into alcoholism, but a confrontation with Erwin's sister at the hospital instead inspires Stark to use the new 'Silver Centurion' armor and take the fight to Stane once again. Stark confronts Stane on the property of Stane International and defeats Stane's agents, including the Chessmen, who had proven a match for his previous armor. Stane dons the Iron Monger armor and confronts Stark personally. The Iron Monger is more powerful than the previous Iron Man armor, but not the Silver Centurion model, which includes such features as the ability to absorb the heat from the Iron Monger's thermal rays and channel it into the armor's own energy supplies. Stane tries to defeat Stark by tricking him into entering a room where Happy, Pepper, and Bambi are being held in suspended animation tanks that could sustain them for months; the walls of the room were covered with photo-electric cells that would trigger a circuit sending 200,000 volts into their bodies if Stark moved, leaving him with no choice but to stand in the room and starve to death to keep them alive. Fortunately, however, Stark is standing directly opposite the room's power source, allowing him to use the weapons in his chest-plate to destroy it. Having freed his friends, Stark then confronts Stane, who is holding his last card: the baby of the woman whom Stark had befriended while on skid row. Stane tells Stark to remove his helmet or he would crush the baby between his palms. Stark, having detected interfering frequencies in his armor's systems throughout the battle, deduces that Stane isn't experienced enough to pilot the armor without some help in the form of an external computer. He uses his armor's pulse bolts to destroy the nearby building containing that computer, causing Stane's Iron Monger armor to seize up and fall to the ground as Stark swoops in to catch the baby; since Stane based the armor on Stark's old designs, Stark knew that the armor would freeze if it lost the control of an outside source. Stane then removes his helmet and confronts Stark. Stane says defiantly that he has one thing left; the ability to deprive Stark of the enjoyment he'd receive in his enemy's humiliation and defeat. Refusing to be arrested and humiliated, he then raises his hand to the side of his head and, using the repulsor ray beam, disintegrates his skull. Stark later obtains complete control over his own company, which he renames Stark Enterprises.
Obadiah also has a son named Ezekiel Stane.