Derwent World Patents Index (Files 351,352)
Frequently Asked Questions

Derwent World Patents Index File 351 (File 352 in Japan) contains information on over 8 million inventions in patent family records, describing 16 million patents issued by more than 40 countries. Started in 1963 as a chemical patent file, coverage was extended to include all technologies and disciplines in 1974. The database provides informative titles and abstracts prepared by Derwent staff who are expert in the particular areas of technology covered by the invention. Additional in-depth indexing for chemical patents (from 1963) and electrical patents (from 1981) is available to Derwent subscribers.

This document addresses some of the most frequently asked questions we have received about the database.

What is the Derwent Accession Number?

The main Derwent Accession Number is a unique number assigned to each record. Derwent Week digits are also part of the display of the main Derwent Accession Number. The Derwent Week appears in the format YYYYWW.

Why doesn't the Patent Family Table download correctly?

Many users have reported receiving output with wrapped rows and misaligned columns in patent family tables that have been downloaded for word processing. Since word-processing programs generally use a variable font, and downloaded records are in fixed font ASCII characters (just like a typewriter!), tabular data can easily become misaligned. Wrapped lines can be corrected easily by using a smaller font size (e.g., font size 10). Misaligned columns can only be corrected by converting the record to a fixed font, such as Courier or Courier New in MS Word.

Is there a format with a simple patent table?

In 1992, the patent family table was extended to include data, such as application number, application date, and the International Patent Class (IPC). The conversion of dates to 8 digits (in preparation for year 2000), longer patent and application numbers, and the addition of application kind have stretched the width of the patent family table to 75 characters.

In order to view a simple patent family table, containing patent number, patent date, and Derwent Week only and omitting patent filing details and subscriber coding, use Format 15 or Format 12. Format 15 contains the simple patent family table and the basic abstract only. Format 12 contains the simple patent family table plus all abstracts. Please note: Formats 12 and 15 are stand-alone formats and cannot be combined with any display tags, such as IM, nor used with the TAG display option.

What does A or U following an Application Number mean?

As part of the enhanced patent family table, application kinds are shown after the application number. Typically, the letters A (application) or U (utility model application) appear. Use of A or U is especially important in countries that have both types of applications and use identical numeric series differentiated only by the application kind.

How should the update codes be used in Alert profiles?

The DWPI database contains numerous update codes that can be used to manage Alert results very precisely. To receive all new records, as well as additions or corrections to existing records in a given update, simply save the search strategy. The default update code, UD=9999, is assumed, so it is not necessary to include it in the Alert profile. However, you can add update precision to your DWPI Alert results by adding one of the following update codes to the final search statement in your profile.

• UB=9999 to receive information about new basic patents only
• UE=9999 to retrieve new equivalents added to existing records
• UM=9999 to retrieve records with newly added chemical codes
• UP=9999 to retrieve records with newly added polymer indexing
• UT=9999 to see existing records with new equivalent abstracts

For help setting up an Alert, contact the Customer Alerts Bureau.

How does chemical segmentation work in DWPI?

To facilitate searching of chemical substances in the Title and Abstract fields, chemical names are processed with a special algorithm that segments chemical terms into the smallest chemically-significant entities. For example, DICHLOROBENZENE can be searched as a complete word, or as any of the three segments, i.e., DI, CHLORO, and BENZENE, and also with partically combined segments, i.e., CHLOROBENZENE. This makes it very easy to locate chemical substances even when you aren't really sure of the order in which the segments might be presented in the chemical name. You can use the W or N operator to retrieve chemical names whether the segments are in the same word or in adjacent words. A special operator, T, lets you locate only those records where all segments are contained in the same word.

Terms that can be whole words or segments can be restricted to the whole word with the suffix /FW. For example, BENZENE/FW retrieves benzene as a standalone word.

For further information...

Detailed information can be found on the Bluesheets for File 351 and 352. If you have further questions, call the Knowledge Center at 800-334-2564 or contact your local representative. Or send e-mail to .