this step include obvious expressive interpretations of broad ideas, elements dictated by efficiency or external considerations, elements in the public domain and industry standards. In the comparison step the court decides whether there is enough similarity between the remaining elements to constitute infringement, and if so the severity of the infringement. One effect of the Altai case may have been that companies that thought they were protected under Whelan, and had therefore not filed patent applications, now found themselves exposed. The Altai case may have gone too far, in effect removing protection from all but the literal elements of a program and thus leading to underprotection. Aware of this risk, many courts that followed the Altai ruling seem to have in practice performed less filtration than was required by the test. However, most circuits have accepted Altai in preference to Whelan. Later decisions Both the code and the "look and feel" of a software product have structure, sequence and organization. Technically there is little or no connection between the two. The same look and feel can be created by entirely different software products, and two internally very similar software products may present very different look and feel. However, the courts have tried to maintain common standards and tests for both types of SSO. Following the 1986 Broderbund ruling, Lotus Development Corporation sued two competing spreadsheet program vendors for copying the look and feel of their Lotus 1-2-3 spreadsheet program, and Apple Computers sued Microsoft and Hewlett-Packard for copying the Macintosh operating system's use of icons, pull-down menus and a mouse pointing device. Both companies drew criticism, since key elements of their look and feel had been introduced earlier by VisiCalc and Xerox. A 1992 federal court finding against Apple largely rejected the idea that copyright law could protect look and feel. The Lotus case went to the Supreme Court, which could not reach a decision, thus by default confirming the lower court's 1995 declaration that the words and commands used to manipulate the spreadsheet were a "method of operation", which is not subject to copyright. Only patent law can protect the behavior of a computer program. Competitors may create programs that provide essentially the same functionality as a protected program as long as they do not copy the code. The trend has been for courts to say that even if there are non-literal SSO similarities, there must be proof of