Lingo - Copyright
The exclusive right, granted by law for a stated period, usually until 70 years after the death of the surviving author of the work, to make, dispose of, and otherwise control copies of literary, musical, dramatic, pictorial and other copyrightable works. The exclusive right is set forth in the 1976 Copyright Act Section 106.
Well, as you probably alrady know, you can’t copyright titles, turns of phrase or arrangements, only compositions. There is no “legal maximum” # of notes or bars you can sample or incorporate into a new composition without penalty. Each claim of infringement is evaluated on a case by case basis. The “Close Encounters” theme has only 5 notes, but it’s copyrighted. There are fewer loopholes in copyright law now than there ever have been. The early days of hip hop made a mockery of copyright law, with albums basically put on the market without clearing a single sample, and waiting for someone to allege theft before they paid. Now albums get release dates delayed because of sample clearance.
And by the way, there is no “legal theft”...