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M NBS TECHNICAL NOTE 834

U.S. DEPARTMENT OF COMMERCE / National Bureau of Standards

• ifcUiUUmmun

Within the U.S. Patent Office
NATIONAL BUREAU OF STANDARDS

The National Bureau of Standards 1 was established by an act of Congress March 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology

and facilitate their effective application for public benefit. To this end, the Bureau conducts

research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau consists of the Institute for Basic Standards, the Institute for Materials Research, the Institute for Applied Technology,

the Institute for Computer Sciences and Technology, and the Office for Information Programs.

THE INSTITUTE FOR BASIC STANDARDS provides the central basis within the United

States of a complete and consistent system of physical measurement; coordinates that system

with measurement systems of other nations; and furnishes essential services leading to accurate and uniform physical measurements throughout the Nation's scientific community, industry, and commerce. The Institute consists of a Center for Radiation Research, an Office of Measurement Services and the following divisions: Applied Mathematics — Electricity — Mechanics — Heat — Optical Physics — Nuclear

Sciences 2 — Applied Radiation * — Quantum Electronics a — Electromagnetics 3 — Time

and Frequency ' — Laboratory Astrophysics n — Cryogenics ". THE INSTITUTE FOR MATERIALS RESEARCH conducts materials research leading to improved methods of measurement, standards, and data on the properties of well-characterized

materials needed by industry, commerce, educational institutions, and Government; provides

advisory and research services to other Government agencies; and develops, produces, and

distributes standard reference materials. The Institute consists of the Office of Standard Reference Materials and the following divisions: Analytical Chemistry — Polymers — Metallurgy — Inorganic Materials — Reactor

Radiation — Physical Chemistry.

THE INSTITUTE FOR APPLIED TECHNOLOGY provides technical services to promote

the use of available technology and to facilitate technological innovation in industry and Government; cooperates with public and private organizations leading to the development of

technological standards (including mandatory safety standards), codes and methods of test; and provides technical advice and services to Government agencies upon request. The Institute consists of a Center for Building Technology and the following divisions and offices: Engineering and Product Standards — Weights and Measures — Invention and Innovation — Product Evaluation Technology — Electronic Technology — Technical Analysis — Measurement Engineering — Structures, Materials, and Life Safety * — Building

Environment * — Technical Evaluation and Application * — Fire Technology.

THE INSTITUTE FOR COMPUTER SCIENCES AND TECHNOLOGY conducts research and provides technical services designed to aid Government agencies in improving cost effec- tiveness in the conduct of their programs through the selection, acquisition, and effective

utilization of automatic data processing equipment; and serves as the principal focus within

the executive branch for the development of Federal standards for automatic data processing

equipment, techniques, and computer languages. The Institute consists of the following

divisions: Computer Services — Systems and Software — Computer Systems Engineering — Information Technology.

THE OFFICE FOR INFORMATION PROGRAMS promotes optimum dissemination and

accessibility of scientific information generated within NBS and other agencies of the Federal Government; promotes the development of the National Standard Reference Data System and

a system of information analysis centers dealing with the broader aspects of the National Measurement System; provides appropriate services to ensure that the NBS staff has optimum

accessibility to the scientific information of the world. The Office consists of the following

organizational units: Office of Standard Reference Data — Office of Information Activities — Office of Technical

Publications — Library — Office of International Relations.

1 Headquarters and Laboratories at Gaithersburg, Maryland, unless otherwise noted; mailing address Washington, D.C. 20234.

3 Part of the Center for Radiation Research.

3 Located at Boulder, Colorado 80302.

* Part of the Center for Building Technology.
Information Handling Needs

Within the U.S. Patent Office

rM-??/

Seymour Jeffery K2e<^£l /?j? y-?

Systems and Software Division

Institute for Computer Sciences and Technology

National Bureau of Standards

Washington, D.C. 20234

*<**AU 0* *

U.S. DEPARTMENT OF COMMERCE, Frederick B. Dent, Secretory

NATIONAL BUREAU OF STANDARDS, Richard W. Roberts, Director

Issued June 1974
National Bureau of Standards Technical Note 834

Nat. Bur. Stand. (U.S.), Tech. Note 834, 17 pages (June 1974) CODEN: NBTNAE

U.S. GOVERNMENT PRINTING OFFICE

WASHINGTON: 1974

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 (Order by SD Catalog No. C13.46:834). Price 55 cents.
PREFACE

The U.S. Patent Office presents a unique challenge to current

information handling technology. Under present law, the Patent

Office must examine every patent application to corroborate the

applicant' s claim to the invention of a useful and non-obvious

machine, process, or composition of matter. To aid its examiners in

this highly intellectual, almost judicial, task, the Patent Office

maintains a file of technical documents representing the citable

corpus of the- "prior art."

To assist the Patent Office in their objective, the Institute

for Computer Sciences and Technology recently analyzed the Patent

Office's requirements and the current state of the art in information handling technology pertinent to these requirements. This

paper examines aspects of the Patent Office's needs that make it

different from other existing information retrieval systems. The

paper then reviews current technology and assesses its ability to

provide effective and economical tools to aid the Patent Office.

The basic information in this paper was presented in a seminar

to the Assistant Secretary of Commerce for Science and Technology

,

Dr. Betsy Ancker-Johnson, during the NBS-in-Action series on June 26, 1973.

Hi

INFORMATION HANDLING NEEDS WITHIN

THE U.S. PATENT OFFICE

S . Jeffery

ABSTRACT

This paper examines aspects of the Patent

Office's needs that make it different from other

existing information retrieval systems. The paper

then reviews current technology and assesses its

ability to provide effective and economical tools

to aid the Patent Office.

Key Words: Administrative operations t data handling;

data storage and retrieval', information handling

technologyy information processing', intellectual

process! patent examination', Patent Office', patent

storage', production statistics.

The United States Patent Office ranks among the world's large

information processing organizations . Each day it performs banking

functions—including demand-deposit accounting—the functions of a post office, a major mail order organization, a large printer, a large manufacturer with significant inventory control, a recorder of

deeds, and a technical library of unique size in almost any dimensions

by which one measures libraries. This entire system of diverse functions exists to support the intellectual —almost judicial—process of

awarding patents.

Challenge to Information Handling Technology

The tasks of the Patent Office present a challenge to current

information handling technology, and include examination of the applications, determining patentability , issuing valid patents, maintaining

a library, and disseminating teachings. The Patent Office annually

processes about 110,000 applications, which include 1.2 million claims.

An average patent is about six pages in length and contains approximately 25,000 characters of text, plus drawings.

A staff of 1200 examiners using a reference file estimated to

include 20 million multi-page documents, conducts the examination

process. Applications in process number 218,000. Over 13 million

printed copies are produced yearly.
These numbers should be viewed in the context of a complex system

of information transfer, from the inventor who presents his teachings

,

through the patent process, to the general public, as a contribution

to the state of the art.

Taken in composite, the process represents a major challenge to

current information handling technology.

Processing Flow

The process can be sub-divided into smaller components that indicate some of the physical aspects of the process. (See Figure 1.)

PATENT OFFICE PROCESSING FLOW

Figure 1.

The arrows can be considered the administrative or process flow.

To be complete , the figure should show a small feedback loop from

"Printing" back to the patent examiners' library, an integral part of

the patent examination process.

2
The Data Handling Problem

One basic problem is the handling of data — the management and

control of a massive paper flow and the maintenance of large bodies of

reference material.

The incoming correspondence (82,000 pieces per week) must be

sorted, checked, and routed to the appropriate area for processing.

This correspondence includes such diverse entitites as:

- 2075 patent applications must be checked for form

and adherence to statutory and office requirements;

- $400-500 ,000 in fees per week in the form of checks and coupons

associated with filing fees and orders for patent copies;

- Applications for certificates of correction;

- Requests for patent copies;

- Correspondence relating to an application being processed.

1650 patents are issued each week. This results in the distribution of a quarter million documents or one and one-half million pages

per week. In addition, 150,000 copies of previously issued patents

are distributed weekly, which include requests for copies from window

sales, standing orders, and examiners.

In the examination process itself, even the data base has immense

proportions. The examiners' file constitutes the bulk of the prior

art which is considered during the examination process. It consists

of an estimated 19 1/2 million documents — including U.S. and foreign

patents and a half million pieces of non-patent literature. It is also

worth noting that there are approximately 6.6 million duplicate and

cross reference copies of U.S. patents.

The public search file contains 9.1* million U.S. patents.

Over many years, the Patent Office has structured its file according to the U.S. Patent Classification System into more than 300 classes

which are further sub-divided into over 90,000 sub-classes. This file

grows continuously and the classification system must be revised to

reflect changing needs of technology.

These structured files are subject to many problems associated

with maintaining their accuracy and completeness. Reference copies

are often removed for detailed examination, and if not refiled correctly, are effectively lost.

* There are 3.75 million original U.S. Patents on file. The number 9.1

million is based on statistical samples of the public search file.
A number of inter-related processes are associated with managing

the massive paper flow and thousands of daily transactions. These

include both managerial and support functions as indicated in

Figure 2.

DATA HANDLING PROBLEM

MANAGERIAL SUPPORT

Scheduling Resources Document Handling

Record Keeping File Storage & Maintenance

Fiscal Transactions Patent Publication and

Distribution

Formal Correspondence Library Services

Figure 2.

Applications of Technology

The application of data processing and automation to the data

handling problems represents not an innovative challenge but rather an engineering task to optimize the application of available manpower,

financial and technological resources. As examples of these applications , consider those performed by the Patent Office to date.

To reduce storage space requirements and to increase file integrity,

the Patent Office has provided microform systems to support archival

files, public search room needs, and patent copy preparation. Photocomposition techniques provided by the Government Printing Office are now used to produce patents and other Patent Office publications . In

addition, this approach produces machine-readable tapes of issued

patents as a by-product.

To ease the problem of gathering management statistics and of

locating individual patents, a card processing "Patent Application

Locator and Monitoring" (P.A.L.M.) system has been installed.

Improvements such as these do help the paper flow and provide

basic support, but they are not really central to the key problem—

that of aiding the patent examination process. Improvement in paper

flow will simply move things into the examination queue faster; an application now spends seven months in this queue before being

assigned to an examiner.

4
Patent Examination —- Input/Output

The Patent Office operates in an environment conditioned by the

goals of reducing pendency while maintaining and improving the quality

of issued patents and* public services. These goals must be achieved

under the constraints imposed by a relatively fixed staff and an in"

creasing number of applications, while also adapting to changing tech"

nology on a worldwide basis.

This high volume of input combined with a relatively fixed staff,

constrains the time available for the prosecution of an individual

case. Currently this amounts to an average of 20 hours per application.

As Figure 3 indicates, in addition to demand, the reference data

base is growing. The ever"increasing size of the examiners' files ~

that is, the prior art — and increasing complexity of inventions in

many art areas, make maintaining a given level of quality difficult.

PATENT EXAMINATION

• GOALS

- DECREASE PENDENCY

TIME

" MAINTAIN/IMPROVE

QUALITY

• OFFICE CONSTRAINTS

- INCREASING DEMANDS

- FIXED STAFF

- CHANGING TECHNOLOGY • EXAMINER ENVIRONMENT

- TIME PRESSURES

- INCREASED COMPLEXITY

OF INVENTION

- RAPID GROWTH OF

RELEVANT PRIOR

ART

Figure 3,
Examination—An Intellectual Process

Patent examination is a complex intellectual process involving a search for concepts . It includes the conceptualization of the inventive point disclosed in the patent application and must precede any

search through the prior art. This conceptualization process requires

intellectual effort, and the examiner must understand exactly what the

invention is and what is claimed. While the inventor has the obligation to reveal his inventive concepts in the specification and drawings

of the application, he usually states his claims in terms which permit

the widest possible interpretation.

Patent Examination — Presearch Activity

The first step is to develop an understanding of the concept of

the claimed invention. Once understood, the examiner must depict the

concept in terms that permit him to access the collection of prior art.

This means he must choose words or phrases to describe the concept

which relate to the manual classification scheme or to the indices of

mechanized search systems.

Figure 4 represents the intellectual process — the understanding

of the "non-obvious" on the left, and the need for basic reference

material in the rectangle on the right.

PATENT EXAMINATION--PRESEARCH ACTIVITY

Review Patent Applications

To

and to

In Order To

NEEDS

COMPLETE COPY OF PATENT

APPLICATION

STANDARD REFERENCE MATERIAL

FOR ART AREA

INDEX TO CLASSIFICATION

CLASS AND SUBCLASS DEFINITIONS

Determine a Search Stra tegy

to Loca te Relevant References

In the Prior Art.

Figure 4
Patent Examination — Search Activity

The search activity itself is an iterative and interactive process

(See Figure 5) . Given a search strategy, the examiner is interested

in sub-setting the prior art to that portion offering the greatest

promise of relevance. This is a screening or scanning task. Both

images and text are involved. In many cases the drawings or equations

are used as an initial key since the associated elements of the "concept" may all be present and discernible.

PATENT EXAMINATION -- SEARCH ACTIVITY

SEARCHES

PRIOR ART

(ITERATIVE

PROCESS)

CLAIM I CLAIM 2

r

NEEDS —

|

READY ACCESS

PAGE IMAGES

HARD COPY

ANNOTATION

REFERENCE

j, LIBRARY

|

Figure 5.

The claims of the application must stand against the full disclosures contained in the prior art. This limits the capability to use

the results of a search based only on abstracts or claims as criteria

for judgment.

The scanning and screening processes appear more tractable to automated solutions than the detailed examination and matching, which are
more intellectual in nature. Examiners have identified the need for

ready access to relevant page images in order to have a continuum from

conceptualization to comparison.

Page images provide the elements of a concept in the context of

the entire disclosure. Hard copy of the prior art allows simultaneous

comparison of a reference set, permits annotation which sets up a clue

path for later iterations, and also allows an analyst to work on a case

basis, at his desk over extended time cycles.

Patent Examination — Official Action

The theme of the previous two figures continues in Figure 6 with

the addition of people-to-people communication.

PATENT EXAMINATION—OFFICIAL ACTION

SUBMITS FINDINGS ON

PATENTABILITY

Through

And

INTERACTI01

WITH

APPLICANT

LIMITS SCOPE

.MODIFIES CLAIM

(ITERATIVE).

NEEDS

nAMENDED APPLICATIONn

CORRESPONDENCE FILE

I I COPIES OF REFERENCES.

PATENT

ISSUED

DENIED

Figure 6
When the examiner determines his search complete — which is a difficult

decision per se — he must complete his conceptualization by making the

judicial-like decision on whether the claimed invention is new and "nonobvious." The examiner must communicate these findings to the applicant's representative and through iterations, find a mutually satisfactory agreement.

Relevance of Technology

As has been seen, the patent examination process includes two

facets. One facet, shown in the rectangle on the right (See Figure 7)

represents mechanical data handling considerations which may be satisfied

by aspects of data processing technology similar to that which is suitable for the Office's administrative and data handling problems . However,

there will be significant system design problems, even at this level.

The other facet is the intellectual process, which requires advanced

application of techniques in the arena called Artificial Intelligence.

RELEVANCE OF TECHNOLOGY

FORMULATION OF STRATEGY

MATCHING OF CONCEPTS

PHYSICAL AVAILABILITY

OF

RELEVANT MATERIAL

ADVANCED APPLICATION OF

TECHNIQUES OF ARTIFICIAL

INTELLIGENCE

MATCH OF DATA HANDLING

TECHNOLOGY TO

OPERATIONS

Figure 7.

Application of Technology

Examining the progress made in research on pattern recognition,

semantic analysis , theorem proving, problem solving and other techniques related to artificial intelligence indicates that this class

of technology is not ready for application to the patent process.
None of the automatic indexing and automatic classification techniques is proven for the Patent Office requirements — particularly in

light of the massive and changing data base.

Automatic "natural language understanding" is still not feasible.

The query language systems of today have problems in providing suitable

response times for very large data bases and also place a burden on the

examiner to express concepts in a way which will subset the prior art

without missing obviously relevant material.

Digital processing of images has a long road to travel before it

reaches practical or economic utility.

In specialized areas, information science and data processing

technology can aid the patent examiner. Examples include coordinate

indexing systems which have proven particularly useful in the computer

art area, structure searching in the chemical art area, and human

assisted computer aided indexing, specialized data retrieval systems

such as Chemical Abstracts and mini-computers in support of administrative and search tasks.

Machine readable and machine viewable patents are now available

and provide basic support to some applications. In addition, they

will facilitate further research and experimentation in adapting

techniques to the patent process, which could eventually become

operational. v Although the entire search problem can't currently be solved,

there are techniques which can be of direct aid to the examiner , in

particular art areas. Two examples of such aids currently in use are:

Chemical Abstracts . In the specialized area of chemical searching, one such aid is the Chemical Abstracts Service. Professional

abstracters prepare highly structured information to form a machinereadable data base. This computerized data base contains not only

bibliographic information, but also a very sophisticated chemical

compound registry system with which it is possible to do chemical

structure searching.

It is anticipated that professional abstracters, using terminals,

will be able to use such a system to edit and modify structural

diagrams in the process of chemical subject indexing and searching.

New York Times . In another specialized area — that of searching

newspaper morgue clippings — the New York Times Information Bank

also used professional indexers and abstracters to support automated

information retrieval functions on interactive terminals.

10
At the core of patent examination is a complex and little understood intellectual process for which current data processing offers

little promise. Around this core of intellectual tasks is a diversified array of support functions , characterized by massive data handling

and process control functions. It is here that data processing technology can assist in managing the support functions. The Patent

examiner can be provided with special purpose tools and aids that can increase the availability of the resources he needs.

Summary

In summary, although technology is not ready to solve the whole

patent examination problem, there are specialized areas in which automation capabilities are applicable. A word of caution, though —

There is no one solution likely to satisfy the diverse requirements of

the Patent Office,

The information processing and data handling needs of the U.S.

Patent Office would be best satisfied by a complex of systems which are

embedded in the examining, documentation and administrative operations

of the office.

Many have suggested schema that would provide enhanced or even

novel public services. Though in many instances current technology

would support such services, these services would not provide direct

or measurable assistance to examination production.

11
BIBLIOGRAPHY

1. Report of the Advisory Committee on Application of Machines to

Patent Office Operations; December 22, 1954; (Bush Committee),

2. The Role of the Department of Commerce in Science and Technology—

The Patent Office; March 2, 1960; (Kelly Committee).

3. Report on the Prospects of Automation in the Search Procedures of

the Patent Office to the Commissioner of Patents; March, 1961;

(King Commi ttee;

4. Report of the Ad Hoc Committee on Patent Documentation; urbach,

Peter F., et al.; May, 1968.

5. An Automated Patent Examination System: Final Report for the U.S.

Patent Office; Wessel, A.E., M.J. Strumwasser, and C.R. Lindholm;

the RAND Corporation, Santa Monica, California 90406; Memorandum

RM-6140-PAT; Contract #8-35187; September, 1969.

6.- Computer-Aided Classification , Report of the Planning Committee;

U.S. Patent Office; August, 1970.

7. Project POTOMAC Patent Office Techniques of Mechanized Access and

Classification, PROGRAM ISSUE STUDY PART ONE: INITIAL BENEFIT COST

ANALYSIS; Nugent, W.R.; July 16, 1971.

8. Design of an On-Line Query Language for Full Text Patent Search;

Glantz, Richard S.; MITRE Corporation, Bedford, Massachusetts;

Contract #1-35539; September 28, 1972.

9. Report Number One: Requirements of the Patent Office Amenable to

Automation; Berg, J.L., B.A.S. Marron, S. Jeffery, G.W. Findley;

National Bureau of Standards, Washington, D.C.; March, 1973.

10. Report Number Two: Status of Project POTOMAC; Berg, J.L.

B.A.S. Marron, S. Jeffery, G.W. Findley; National Bureau of

Standards, Washington, D.C.; April, 1973.

11. Report Number Three: Feasibility of Project POTOMAC; Berg, J.L.,

C. sheehan, J. Clapp, S. Jeffery; National Bureau of Standards

,

Washington, D.C.; May, 1973.

12. Report Number Four: NBS Recommendations—Project POTOMAC;

Berg, J.L., B.A.S. Marron, C. Sheehan, S. Jeffery; National Bureau

of Standards, Washington, D.C.; June, 1973.

12
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