4.2.2.2 Classification Priority Rules

Also in this Chapter:

• 4.2.2.1 Invention Information and Additional Information​​​​​​​
• 4.2.2.3 Classifying in Function-Oriented and Application-Oriented Places
• 4.2.2.4 Classifying Chemical Compounds
• 4.2.2.5 CPC Classification Rules
• 4.2.2.6 Classification using C-sets

Sub-chapters:

• 4.2.2.2.1 Common Rule
• 4.2.2.2.2 First Place Priority Rule

• 4.2.2.2.3 Last Place Priority Rule

• 4.2.2.2.4 Special Rules

• 4.2.2.2.5 Classifying a Combination of Technical Subjects

Priority rules provide guidance on where to classify subject-matter in cases of overlap. This situation is very common among the subgroups of a main group, so it is not practical to introduce explicit precedence rules every time it occurs.

If more than one subgroup fits the subject-matter, then either a common rule (the default rule), a first-place priority rule or a last-place priority rule is applied. If a classification area has an applicable classification rule, such rule is usually indicated clearly in the Notes.

If technical subjects are covered by only one (sub)group, classify only in that group subject covered by more than one (sub)group, rules are applied following this order:

1. Common rule
2. First place priority rule
3. Last place priority rule