The same goes for utility ([Edit: providing typically, when valuable, broad] protection of gadget, process, [Edit: software], etc.) patents: http://robertplatt

The same goes for utility ([Edit: providing typically, when valuable, broad] protection of gadget, process, [Edit: software], etc.) patents: http://robertplattbell.blogspot.com/2007/10/file-early-file-often.html http://robertplattbell.blogspot.com/2007/10/file-early-file-... In Pfaff, Justice Stevens wrote: "Second, the invention must be ready for patenting. That condition may be satisfied in at least two ways: by proof of reduction to practice before the critical date; or by proof that prior to the critical date the inventor had prepared drawings or other descriptions of the invention that were sufficiently specific to enable a person skilled in the art to practice the invention." (Id., at 12) All one has to do is show how one skilled in the art can build the thing (or perform the process). The actual building of a working model is not legally necessary. By the way, these are the current (2004) USPTO utility-patent categories: http://www.uspto.gov/go/taf/govt/class_list/class_name_gov.htm http://www.uspto.gov/go/taf/govt/class_list/class_name_gov.h... Unlike utility patents, design patents are usually narrow, and therefore [Edit: usually] worthless: http://robertplattbell.blogspot.com/2007/10/different-patent-types.html http://robertplattbell.blogspot.com/2007/10/different-patent... A design patent only covers the ornamental outward appearance of an article of manufacture and thus provides very narrow protection.