Patent Drawing Requirements in the US and Europe [Latest Guidelines]

General patent drawing requirements, uspto logo

Many inventors first apply for a patent in the US, and then seek the same patent protection in Europe. Both the US Patent and Trademark Office (USPTO) and the European Patent Office (EPO) affirm the importance of drawings to patent applications.

The USPTO says drawings are required if they are needed to understand the subject matter; they are almost always needed. The EPO emphasizes quality: “Good-quality drawings are very important for the correct disclosure of the invention.”

There are many similarities – and some differences – in the rules for patent illustrations in the US and Europe. The full USPTO requirements can be found online at Nonprovisional (Utility) Patent Application Filing Guide.The EPO requirements can be found at Guide for applicants: How to get a European patent (drawings), with links to additional pages on that page.

Requirement of patent drawings

The USPTO requirements are much more detailed than the EPO requirements.

I would recommend You to read the USPTO requirements for patent drawings.

In the following table we highlight the major differences and some of the similarities. When preparing a patent drawing for submission to either authority, please refer to the specific guidelines from the relevant office, linked above. The table is just to give you an idea of what’s different.

	USPTO	EPO
Paper Size	8.5” x 11” (21.6 x 27.9 cm)	A4 (29.7 cm x 21 cm). Further specifies paper must be used in upright position, and must be pliable, strong, white, smooth, matt and durable.
Margins	top 1” (2.5cm) left 1” (2.5cm) right 5/8” (1.5cm) bottom 3/8” (1cm)	The same
Ink and lines	India ink or equivalent solid black lines	…durable, black, sufficiently dense and dark, uniformly thick and well-defined lines and strokes.
Electronic submissions	Sheets submitted electronically in PDF; drawings made by hand should be scanned into PDF	There is an online form. 95% of patent applications at EPO are submitted electronically. Drawings and other materials are submitted in PDF format.
Photographs	Photos not normally permitted; black and white photos OK if ink drawings won’t show properly. Color photos require special approval, same as color drawings.	Photos are permitted. Color photos are scanned and converted to black and white.
Other types of figures	Chemical or mathematical formulas, tables, computer program listings, and waveforms may be submitted as drawings and are subject to the same requirements as drawings.	Flow sheets and diagrams are considered drawings.
Numbering	Sheets may be numbered with consecutive Arabic numerals placed in middle of the top of the sheet, or right-hand side. Number of sheets are also indicated, e.g., “1/5.” Views are numbered in consecutive Arabic numerals, preferably in the order in which they appear on the drawing sheets. View numbers are preceded by “FIG;” e.g., “FIG 1.” Where there’s only one view, leave off the numbering.	Sheets must be numbered in consecutive Arabic numerals, centered at the top of the sheet, but not in the top margin. The different figures shall be numbered consecutively in Arabic numerals, independently of the numbering of the sheets.
Letter/number size	Print size of at least 1/8” (.32cm	Same
Text		No text except if short keywords are indispensable to understanding the drawing (e.g., “steam,” “air,” etc.). Must be placed in such a way that they can be replaced with a translation without interfering with any lines of the drawing.
Reference characters	Do not include any reference characters that are not mentioned in the description; be consistent in use of a given reference character.	Same
Corrections	Amendments are not allowed to include any new matter.	Same.

Conclusion

Every patent office has very specific requirements for patent drawings. When adapting a patent application from one jurisdiction for submission to another jurisdiction, special care must be taken to make sure the drawings being submitted comply with all the rules of the relevant patent office.

Failure to comply with all of the patent drawing regulations may result in your application being delayed or denied.