UNITED STATES PATENT OFFICE

THE CLASSIFICATION OF PATENTS

WASHINGTON
GOVERNMENT PRINTING OFFICE
1915

PREFATORY NOTE.

Parts A and B of the following pages are designed to acquaint all persons using the Patent Office classification with the principles upon which the reclassification is proceeding.

Part C consists of a few tentative rules advanced with the notion of fixing classification practice within the office in certain doubtful cases.

Part D is intended to inform examiners reclassifying within examining divisions respecting the initial procedure in reforming a class.

CONTENTS.

1. A. Introduction. 1
   
   • Past classifications of the U. S. Patent Office. 1
   • Beginning of revision. 2
   • Precedents and authorities. 3
   • Definition of scientific classification. 4
2. B. Principles of the new classification of the Patent Office. 4
   
   • Elements of a Patent Office classification. 4
     
     • Basis of classification. 5
       
       • Art as a basis. 5
       • Function or effect as a basis. 7
       • Structure as a basis. 8
     • Division and arrangement. 9
       
       • Infinitude of possible combinations. 10
       • Division and arrangement in the natural sciences. 10
       • Difficulty of entitling a subclass corresponding to every combination.11
       • Expedients to reduce the number of subdivisions. 12
       • Superiority and inferiority. 15
       • Definite positional relationship of subdivisions. 16
       • Indented schedules. 17
       • Bifurcate division. 19
       • Utility of arrangement according to resemblances. 19
     • Definition. 20
     • Cross-references and search-notes. 21
     • Diagnosis to determine classification. 22
       
       • Claimed or unclaimed disclosure. 22
       • Diagnosis of pending applications. 23
       • Difficulties due to varying ideas of claims. 25
3. C. Rules of classification. 26
   
   • Basis of classification. 26
     
     • 1. "Art" as the basis. 26
     • 2. Operative or manipulative