Tony Rowles.
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Patent Citation Tool

Highlight text on Google Patents. Get its column and line citation, without opening the PDF and counting lines.

Install
Chrome Web Store ↗Firefox (latest release) ↗
Stack
JavaScript, Chrome & Firefox extensions, PDF.js, Cloudflare Workers, Cloudflare KV, Vitest
Source
github.com/tonyrowles/patent-cite-tool

Try it

highlight any text on the page
US 9,876,543 B2Sample text for demonstration
5
In one embodiment, the fastening assembly 100
includes a housing 102 and a retaining clip 104
that is slidably received within a channel 106
formed in the housing. The clip may be formed of a
resilient polymer, such that the clip deflects
when a user applies force to a release tab 108 and
returns to its original position when the force is
removed. As shown in FIG. 3, the channel 106
extends along a longitudinal axis of the housing
and includes a pair of detents 110 that engage
corresponding recesses in the clip. Engagement of
the detents with the recesses resists unintended
movement of the clip during use, while still
permitting deliberate removal by the user. In some
embodiments, a biasing member such as a coil
spring 112 urges the clip toward a locked
position.
6
Referring now to FIG. 4, a method 200 of
assembling the fastening assembly begins at step
202, in which the retaining clip is aligned with
an opening of the channel. At step 204, the clip
is advanced along the channel until the detents
snap into the recesses, producing an audible and
tactile indication that the clip is seated. At
step 206, the assembly may be tested by applying a
predetermined load to the release tab and
confirming that the clip remains engaged. It will
be appreciated that the steps of method 200 may be
performed in a different order, and that certain
steps may be omitted or combined without departing
from the scope of the present disclosure. The
embodiments described above are illustrative only
and are not intended to limit the claims.
citationnone yet

The problem

Office actions and briefs cite issued patents by column and line, as in “col. 5, ll. 12-14.” Google Patents shows a patent’s text but not its printed pages, so finding a citation means opening the PDF and counting lines by hand.

What it does

Highlight a passage on Google Patents and the extension gives you its citation. Published applications get paragraph numbers, like ¶ [0042], straight from the page.

The citation can appear in a small button next to the selection or as soon as you finish selecting, come from the right-click menu, or be added to whatever you copy with Ctrl+C. It can also lead with the patent number, as in “’123 patent, col. 5, ll. 12-14.”

How it works

The extension downloads the patent’s PDF and reads it with PDF.js in the background, recording where every line of text sits on the printed page. It then finds the words you selected in that layout to get the column and line.

Operator-prepared position maps are cached in Cloudflare KV to speed up supported lookups. When a map is not available, the extension parses the PDF locally. If Google’s PDF server is down, a Cloudflare Worker gets the patent from the USPTO instead.

I check its accuracy against 71 patents with known-correct citations.

Install the extension

For Chrome, open the Patent Citation Tool listing in the Chrome Web Store and choose Add to Chrome.

For Firefox, download patent-cite-firefox.zip from the latest GitHub release and extract it. Open about:debugging, choose This Firefox, then Load Temporary Add-on and select the extracted manifest.json. This temporary installation lasts until Firefox restarts.

The GitHub README also covers building and loading the extension from source.

A citation example

  1. Open an issued US patent on Google Patents and wait for the extension to finish reading its PDF.
  2. Highlight a passage in the specification and use the citation button or right-click menu.
  3. Copy the result into your draft. A passage spanning lines 12 through 14 of column 5 would produce a citation such as col. 5, ll. 12-14.

That example illustrates the format; the column and line numbers depend on the passage you select. For a published US application, the result uses the page’s paragraph number instead, such as ¶ [0042].

Supported documents and limits

The extension is built for issued US patents and published US patent applications on Google Patents. Column and line citations depend on matching the selected words to text extracted from the issued patent’s PDF. Paragraph citations depend on the application’s paragraph markers.

The first lookup may take time while the PDF is downloaded and parsed. Unusual layouts or text that cannot be extracted or matched cleanly may prevent a reliable result. Check the cited passage against the patent before using it in a filing. Foreign patents and other document types are outside the scope described here.