Actually, both Gates and Jobs stole the interface from Xerox. Gates had the smarts to get them to sign them away.
Not true. Here is a link to the true story of what happened between Xerox and Apple. Here, also is an account from Bruce Horn, someone who was there, both at Xerox and later at Apple.
That's an urban legend. Read below:
In the late 1970s, Apple was experiencing meteoric growth in the mists of the success of the Apple II and significant private investment. Bill Atkinson, a software genius in charge of the Lisa project, convinced Steve Jobs to take a look at the possibilities of the PARC Alto.This gets posted on every Apple thread, so I just keep the facts saved where I can repost them.Jobs was so struck by the power inherent to the PARC that he offered Xerox the opportunity to invest a million dollars in Apple computer if the company would agree to let him and his Lisa team study Alto. Xerox felt that it had nothing to lose. After all, they couldn't sell it. They did not believe the world was ready for the advanced PARC technologies. Apple was about to go public and Xerox's investment branch, Xerox Development Corporation, sensed an opportunity to turn a quick profit. Xerox invested $1 million in Apple by purchasing 100,000 shares at $10 each. Furthermore, Xerox signed an agreement with Apple to never purchase more than 5 percent of Apple's outstanding shares. Within a year, these shares split into 800,000 worth $17.6 million when Apple went public.
With Xerox's cooperation, the Apple team twice visited the PARC facility. Jobs was ecstatic and immediately instructed the Lisa development team to begin working on a graphical operating environment like that of the Alto. The Lisa project was to be Apple's first attempt to built a computer around a graphical operating system and many of its technologies would later find their way to the Macintosh. Unfortunately, the Lisa, aimed primarily at high-end business users, never found commercial success. It has often been suggested that Apple's development of the Lisa GUI primarily centered around copying the Alto GUI. This shortchanges the hard work and brilliance of the Lisa team. Apple did not receive a blueprint from Xerox. What they got was much more profound: inspiration. Xerox had nothing to complain about. They had this wonderful creation that they couldn't sell. A 1760% increase on a one million dollar investment for two peeks at the PARC Alto was about the best the company could have hoped to achieve.