Patent Drawings (Utility Applications). Episode 14
- Adam Diament
- Mar 15
- 3 min read
This podcast focuses on patent drawings for a utility patent, not a design patent. I’ll cover design patents and their drawings in another episode.
The first thing you should know about patent drawings is that you probably shouldn’t do them yourself. Even if you draw well, the Patent Office likely won’t accept your drawings because of the many strict rules governing what is required and what is prohibited.
I like to do my drawings after drafting the claims, rather than starting with the written description. Once you have your drawings, it becomes much easier to write the rest of your application since you can reference and describe every part in detail.
Patent Drawing Requirements
This is a technical episode because patent drawings are subject to many precise requirements. If you want to review the official rules, Google "37 CFR 1.84" to find them.
I will cover four major categories of requirements:
Page Requirements
Rules for Drawing the Invention
Labeling Rules
Line Rules
There are exceptions to some of these rules, but following them reduces the chance of objections rather than relying on exceptions.
1. Page Requirements
Drawings must be on 8.5 x 11 inches or A4 paper.
Margins must be at least:
2.5 cm (top and left)
1.5 cm (right)
1 cm (bottom)
To simplify this, I use 1-inch margins all around.
The Patent Office prefers drawings in an upright vertical orientation, but if your invention is wider than it is tall, you can rotate the page horizontally.
2. Rules for Drawing the Invention
Include as many drawings as necessary to show all parts of your invention.
Most inventions require multiple views of the same embodiment.
Cross-sections or exploded views may be necessary to show internal components.
Standard views in patents include:
Top view
Bottom view
Side view
Front view
Rear view
Perspective view
Cross-sectional views
Exploded views (showing separated parts)
To see examples, search Google Patents for U.S. Patent 8726799 (the avocado slicer patent). I will reference it throughout this episode.
3. Labeling Rules
Sheet Numbering
Each sheet must be labeled with two numbers:
The sheet number (e.g., 1, 2, 3, etc.)
The total number of sheets
Format: "1/5", "2/5", "3/5", etc.
Place the numbering at the top center (but not in the margin).
Figure Numbers
Each figure should be labeled with "Fig." followed by a number.
Example: Fig. 1, Fig. 2, Fig. 3
Figures can be placed on the same page if they fit, but must remain clear.
Reference Numbers
Do not use words in your drawings unless absolutely necessary.
Instead, use reference numbers:
Place a number near each part and draw a line pointing to the part.
Use even numbers to allow room for additional elements later.
In the written description, every mention of a part should include its reference number.
Example: In Fig. 3 of the avocado slicer patent, reference number 302 points to a slicing blade.
In the written description, every mention of "slicing element" is followed by (302).
Over-label rather than under-label—even simple inventions might have 50+ labeled parts.
Use consistent numbering across all figures:
If a slicing blade is 302 in Fig. 3, it should also be 302 in Fig. 4.
Text Size Recommendations
While there are formal size rules, I use:
Size 12 for reference numbers
Size 16 for sheet numbering
Size 36 for figure numbering
4. Line Rules
Place reference numbers near the part, but not directly on top of it.
Use lead lines to connect reference numbers to parts:
Leave space between the number and the part.
Lead lines should not cross each other—think of the "Ghostbusters Rule" ("Don’t cross the streams!").
Lead lines can be curved or straight:
Curved lead lines help distinguish them from the invention itself.
Arrow Use:
No arrows for specific parts (e.g., "blade 302").
Use arrows to indicate general regions or specific surfaces.
Example: In the avocado slicer patent, reference number 280 (a knife) has an arrow pointing to the general knife region.
Other numbers, like 292 (first edge) and 294 (second edge), do not have arrows because they refer to specific parts of the knife.
Should You Do Your Own Drawings?
Probably not. Even patent attorneys typically hire professional patent illustrators.
Cost: Drawings usually range from $20 to $50 per page, depending on complexity.
Total cost: Even with 10 drawings (on the high end), you might spend $500—a small investment considering the importance.
Attempting it yourself will likely result in objections, requiring revisions that could cost even more.
Final Thoughts
If you want help drafting your patent application and drawings, I offer these services through my practice at Diament Patent Law. I’m Adam Diament, and until next time, keep on inventing!
