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Writing a patent application (page 3 of 8)

From: Canadian Intellectual Property Office


You must send us all patent documents in the correct format or they will be rejected. There are strict rules regarding the quality of the paper, the size of the margins, the size of the text and the page layout. Most word processors can handle these requirements.

You can send your patent application in either French or English. However, the abstract, description, claims, and drawings must all be in the same language.
Here is the format we expect for text:

(There are other rules for drawings.)


Use good quality white paper that is either 21.6 cm by 27.9 cm or 21 cm by 29.7 cm (A4 format). The paper should not be creased or folded. The Patent Office has to be able to reproduce it electronically, so you must use normal fonts and avoid fancy styles. Your application should not show any underlining, erasures or corrections.


Use the following margin dimensions:

The only things you can write in the margins are the file reference number (in one of the upper corners) and the line numbering for the description and claims (left margin).


The capital letters of the text should be at least .21 cm high. A font size of 12 pt. is usually enough. Except for sequence listings, tables and mathematical and chemical formulas, the text for the description and claims should be spaced 1.5 lines apart.


Number the pages of the description and claims sections in order at the centre of the top or bottom of the page. You can number the lines of the description section in the left margin. Number each claim in order.

Page layout

In most cases the page layout is upright (portrait orientation). If it helps to present the information, you can format the drawings, formulas and tables using a landscape orientation.

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