2001-09-04 = Start date of this file by Jean Roth, jroth@nber.org 2004-10-01 -- U.S. Patent Classification System (USPCS)(as of December 31, 2002) and 41 unique product fields based on the 1972 Standard Industrial Classification System (SIC) Concordance link added. Link: ftp://ftp.uspto.gov/pub/taf/sic_conc/ Data file is sic_co02.exe. There is also a U.S. to IPC lookup at http://www.uspto.gov/go/classification/ 2004-09-39 -- 312 of the match observations do not have cusip matches. Reasons unknown. 2002-01-07 -- The lines in the ASCII CSV files are terminated by the newline character "\n". "CSV" stands for comma separated values. All values in the ASCII CSV files are separated by commas. In addition, the character values are enclosed by double quotes. MySQL sets missing values of numeric variables to '0' and missing values of string variables are set to the empty string. See http://www.mysql.com/doc/en/LOAD_DATA.html for more information. 2002-12-11 -- class_match and subcategory file added 2002-08-29 -- 338 observations added to match.zip and amatch.zip files 2002-06-11 -- International links added 2001-10-04 -- ASCII CSV data added 2001-09-04 -- SAS .tpt data added There are three types of patents: utility, design, and plant. Utility patents are for inventions. Design patents are for ornamental designs, and plant patents are for new varietites of plants.