At the time, Michael Douglas was better known as a producer. Oliver Stone was warned that Douglas would micromanage the film and undermine Stone. Stone hired Douglas anyway, and Douglas did not micromanage.
Oliver Stone later admitted that everyone involved told him Daryl Hannah was miscast, but he was too proud to replace her. This caused tension on set, particularly with Sean Young who wanted the role herself.
From the beginning, Sean Young kept telling Oliver Stone that she should play Darien and Daryl Hannah should be fired. Young would show up on the set late and unprepared. It's part of the reason her role is so small.
Oliver Stone wanted to make a film about the 1950s quiz show scandals. When he tossed around ideas with his friend Stanley Weiser, he hit on the notion of making a film about Wall Street instead. Weiser was reluctant because he knew very little about the financial markets. Stone encouraged Weiser to read "Crime and Punishment" and "The Great Gatsby" for an idea of the morality he wanted to put into the story, and Weiser spent the next few months immersing himself in the financial world. He and Stone spent three weeks visiting brokerage houses and interviewing investors.
Gordon Gekko's "Greed is good" speech was inspired by Ivan Boesky's speech at the University of California's commencement ceremony in 1986. Boesky was a Wall Street arbitrageur who paid a $100 million penalty to the SEC later that year to settle insider trading charges. In his speech, Boesky said "Greed is all right, by the way. I want you to know that. I think greed is healthy. You can be greedy and still feel good about yourself."
Daryl Hannah has never seen the film. She said in an interview that it was a "rough experience" and she and Director Oliver Stone had an "unhealthy working relationship". At the time of filming she accused Stone of being a misogynist. She said "film is a collaborate medium. Sometimes you hook up with people you don't collaborate well with."
Anacott Steel, a fictional company, may be an obscure reference to Anaconda Copper, a company that busted in the 1929 stock market crash. Many entertainers had invested in Anaconda, including Groucho Marx.
Sir Larry Wildman, the British takeover artist played by Terence Stamp, is widely believed to be modeled after Sir Gordon White of Hanson PLC, a company that does only acquisitions, liquidations, and wholesale deconstruction of companies.
The scene where Bud confronts Gekko in his office is primarily composed of two extended takes, separated by the cut to the reverse angle shot of Gordon shouting "Because it's wreckable!" The rest of the scene is one unbroken take.
When Bud Fox discovers the Anacott Steel acquisition, Gordon Gekko tells him to buy 1500 option contracts. When they sell their shares to Sir Larry Wildman, the option contracts provide a gross return of $3,225,000.
At the Teldar Paper shareholders meeting, the name card of the man at the end of the back row on the right, visible over Gordon Gekko's shoulder, says "Sean Stone". Oliver Stone's son, Sean Stone, plays Rudy Gekko.
During the meeting where it's revealed Blue Star will be broken up, Gekko's representative tells Bud he will have the shortest lifespan of any executive, "since that pope who got poisoned." This is obviously a reference to John Paul I whom died in 1978 after only 33 days of being pope.
John Paul I died of natural causes but conspiracy theories still persist of an assassination.
The trivia item below may give away important plot points.
At the end of the movie, when Bud Fox gets out of the car to take a long walk up the stairs to the courtroom, he passes by a newspaper stand in the background with a poster for Fortune magazine. His picture is on the front cover.