Derwent Document Search Fields

Enter one or more patent numbers connected with the OR Boolean search operator. You can enter complete patent numbers or partial patent numbers using wildcards (* $ ?). The following are patent number formats:

Numeric Series Patent Numbers

Format CCNNNNNNNN, where "CC" is the WIPO country code and "N" is the maximum 10-digit serial number.

Patent Numbers that Include a Year Element

Format CCYYYYNNNNNN, where "CC" is the WIPO country code, "YYYY" is either a two-digit year prior to 2001 or a four-digit year from 2001, and "N" is a eight-digit serial number.

Japanese Patent Numbers

Special formats are used to distinguish between Japanese documents that are unexamined applications, old law examined patents and new law granted patents. From January 1, 2001, the Japanese Patent Office introduced a new numbering system for patent applications (A documents) based on the Western Year using YYYY format in place of Imperial years.

Unexamined Applications - Kokai (Patent Kind A,W, X, Y, Z)

Format JPEENNNNNN, where "JP" is the WIPO country code, "EE" is a two-digit Japanese Emperor year, and "N" is a maximum six-digit serial number. For example: JP11280599-A

Format JPYYYYNNNNNN, where "JP" is the WIPO country code, "YYYY" is a four-digit Western year (after January 1, 2001), and "N" is a maximum six-digit serial number. For example: JP2001102423-A

Old Law Examined Accepted Patents - Kokoku (Patent Kind B)

Format JPYYNNNNNN, where "JP" is the WIPO country code, "YY" is a two-digit Western year, and "N" is a maximum six-digit serial number. For example: JP96033614-B2

New Law Granted Patents - Toroku (Patent Kind B2)

Format JPNNNNNNN, where "JP" is the WIPO country code and "N" is a maximum seven-digit serial number. For example: JP2839470-B2

Western Year - Japanese Emperor Year Conversion

Western Year	Japanese Emperor Year
1963 - 1988	Western Year minus 25
1989 - current	Western Year minus 88

The International Patent Classification (IPC) is an internationally recognized classification system that is controlled by the World Intellectual Property Organization (WIPO) and assigned to patent documents by Patent Offices.

In the Derwent Class Codes lists, we have indicated the equivalent IPC in an abbreviated form (for example, A47, F23) against the Derwent class (for example, P2, Q73). However, this should only be taken as a guide, since there are areas where the Derwent class codes are assigned by our subject experts, and no strict correspondence is claimed.

In sections P and Q (Engineering Sections) the correlation between the IPC and Derwent class is exact.

Since the national patent offices may apply IPCs in different ways, the same invention patented in a number of countries can have different IPCs. The Derwent patent family structure solves this problem by assigning the most appropriate Derwent class(es) to the basic patent record. All other members of the family then automatically take the same class(es). The exception to this is for Engineering patents where the classes applied to the equivalent patent may be revised if the IPCs change.

Enter one or more classifications connected with search operators. You can enter complete IPC codes or partial IPC codes using wildcards.

Alternatively, click the search aid link to look for specific IPC codes to add to your search.

Patents are divided into 20 broad subject areas or sections. The sections are grouped into three areas:

• Chemical Sections (A - M)
• Engineering Sections (P - Q)
• Electrical and Electronic Sections (S - X)

They are subsequently divided into 20 broad subject areas or sections. These sections are then further subdivided into classes. Each class consists of the section letter, followed by two digits. For example X22 is the class designation for Automotive Electrics and C04 is the class for all Chemical Fertilisers.

When used in combination with other search fields such as a Topic search, these classes allow you to precisely and effectively restrict your search to the relevant subject area.

Enter one or more three-digit class codes connected with search operators. You can enter complete codes or partial class codes using wildcards.

Alternatively, click the search aid link to look for specific codes to add to your search.

Derwent Manual Codes are assigned to patents by Derwent's indexers. They are used to indicate the novel technical aspects of an invention, and also its applications. Using manual codes to create a detailed search strategy can significantly improve the speed and accuracy of searching.

Manual codes are arranged in hierarchies where there is a broad or general code at the top of the hierarchy followed by subdivisions of the codes into more specific categories.

For example, the manual code J07 is defined as "Refrigeration; ice; gas liquefaction/solidification." The manual code is broken down into four subdivisions:

• J07-A – Refrigeration machines, plants, or systems, combined heating and refrigeration systems
• J07-B – Freezing of (semi)liquids
• J07-C – Refrigerators, cooling, and freezing apparatus
• J07-D – Gas liquefaction, solidification, or separation by pressure or cold

Each of these is further broken down into more specific subdivisions. For instance, J07-B02 is specifically about "ice or snow production for special purposes."

Enter one or more manual codes connected with search operators. You can enter complete manual codes or partial manual codes using wildcards.

Alternatively, click the search aid link to look for specific codes to add to your search.

The Primary Accession Number (PAN) is a unique identification number assigned by Derwent to each document. It consists of the following:

• the year of publication,
• a six-digit serial number, and
• a two-digit update number indicating when Derwent published the patent abstract.

To search for a patent using the PAN, enter the four-digit year, a hyphen, and then the six-digit serial number.

Enter one or more Primary Accession Numbers connected with the OR Boolean search operator. You can enter a complete Primary Accession Number or a partial Primary Accession Number using wildcards.

Searches the Ring Index field within a patent record. Enter one or more numbers connected with search operators. Ring Index Numbers (RIN) are five-digit codes assigned to chemical ring systems. They are searchable in Derwent World Patent Index from 1972 onwards, for patents classified in:

• Section B (Pharmaceuticals)
• Section C (Agrochemicals)
• Section E (General Chemicals)

Searches the Derwent Compound Number field within a patent record. Enter one or more numbers connected with search operators.

Derwent Compound Numbers (DCN) are Merged Markush Service (MMS) Compound Numbers for specific compound entries in the MMS database on Questel.Orbit. MMS compound number indexing is available in Derwent WPI on all Hosts from 1987 onwards for patents classified in:

• Sections B (Pharmaceuticals)
• Section C (Agrochemicals)
• Section E (General Chemicals)

Searches the Derwent Registry Number field within a patent record. Enter one or more numbers connected with search operators.

Derwent Registry Numbers (DRN) are assigned to the most common 2,100 compounds referred to in Derwent WPI. DRN indexing is available in Derwent WPI from 1981 onwards for chemical patents classified in Sections B (Pharmaceuticals) through M (Metallurgy).

Read more about the DCR number.