Public users may perform preliminary searches of patent information in a variety of formats including on-line, microfilm, and print at the United States Patent and Trademark Office (USPTO) Public Search Facility located in Alexandria, VA. State of the art computer workstations provide automated searching of patents issued from 1790 to the current week of issue. Full document text may be searched on U.S. patents issued since 1971 and OCR text from 1920 to 1970. U.S. patent images from 1790 to the present may be retrieved for viewing or printing. Some foreign patent documents are available.