Source : Free On-Line Dictionary of Computing

user interface copyright
     
        There have been several attempts, mostly by big US software
        companies, to enforce patents and {copyright} on user
        interfaces.  Such legal action aims to restrict the use of
        certain command languages or {graphical user interface}s to
        products from one software supplier.  This is undesirable
        because it either forces users to buy software from the
        company whose interface they have learned or to learn more
        than one interface.  An analogy is often drawn with the user
        interface of a car - the arrangement of pedals and steering
        wheel etc.  If each car manufacturer was forced to use a
        different interface this would be very bad for car users.
     
        Following a non-jury trial, which began in early January 1987,
        a federal judge ruled on 28 June 1990 that keyboard commands
        and on-screen images produced by {Lotus Development
        Corporation}'s popular {1-2-3} {spreadsheet} are protected by
        {copyright}.  {Paperback Software International} and
        subcontractor Stephenson Software Ltd. who lost the case,
        argued that the copyright applies only to the inner workings
        of the software.  US District Judge Robert Keeton wrote that
        "The user interface of 1-2-3 is its most unique element and is
        the aspect that has made 1-2-3 so popular.  That defendants
        went to such trouble to copy that element is a testament to
        its substantiality".  Defence attorneys had argued that the
        Lotus commands represented "instructions for a machine rather
        than the expression of an idea".
     
        Soon after this decision, on 2 July 2 1990, Lotus sued
        {Borland International} and the {Santa Cruz Operation} for
        producing {spreadsheet}s (Quattro, Quattro Pro and SCO
        Professional) whose interfaces could be configured to look
        like 1-2-3's.
     
        (1994-11-16)