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Stopwords description

Stopwords are words that are usually not indexed for text paragraphs in Patent Public Search. They give little meaning to a document since they occur so frequently. Stopwords save storage space. When a stopword is used in a query in Patent Public Search, the term is only searched in certain metadata fields, such as assignee name and PCT data. No results are returned if the stopword is found in the text fields/body of the document (for example in the Title, Abstract, Detailed Description, or Claims).

Stopwords in Patent Public Search
a* on
an or*
and* such
are that
as* the
at* their
be* then
by there
for these
if they
into this
in* to
is was
it* will

"*" signifies that the term is a searchable stopword

Searchable stopwords

Uppercase or mixed case stopwords can be searched as they are indexed to support search and retrieval of such terms. The stopwords marked by asterisks in the table above are searchable stopwords that can be found in the metadata and body of a document. Searchable stopwords in the body of the document will only be found/highlighted, if they are upper case or mixed case. For instance, if searchable stopword “and” is searched, the Patent Public Search tool only finds and highlights uppercase “AND” in the body of the document.

Searchable stopwords
A Upper and mixed case
"And" Upper case
As (arsenic) Mixed case
At (astatine) Mixed case
Be (beryllium) Mixed case
IN (indium) Mixed case
IT (information techology) Upper case
"OR" Upper case

Searchable stopwords will be found in any case within the metadata. For example, both uppercase and lowercase “and” will be found/highlighted in the metadata of a document.

“AND” and “OR” are searchable stopwords that are also operators. They should be searched inside quotation marks to transform the operator into a searchable stopword.

If a user searches a stopword that is not searchable, such as “for”, Patent Public Search will warn the user that the word is a stopword and will only be searched in metadata fields.

Example using searchable stopwords

“Vitamin A” AND “and Gate”

Note that the first “AND” in this example is the operator and the second “and” is a searchable stopword that has to be placed inside quotation marks. If “Vitamin A” AND and gate is searched for, the user will receive a Query error, because Patent Public Search is viewing both “AND”s as operators. Putting quotation marks around AND Gate, transforms the second AND into a searchable stopword.

Patent Public Search retrieval examples

(non-stopwords between hit terms are underlined and hit terms are both highlighted and underlined)
Note: The databases do not count stopwords when figuring word proximity.

(analog ADJ digital ADJ computer)

To retrieve “….a single microcomputer analog to digital computer.”
To retrieve “…determines the rate of communication between an analog and a digital computer or as a master oscillator for equipment testing at various frequencies.”

(DNA ADJ3 Computer)

To retrieve “…the digital-DNA, then storing it on the computer’s non-transitory computer storage medium.”
To retrieve “…a target DNA in a sample, for example, computer-implemented methods….”