The Pre-Filing Patent Figure Checklist: 25 Items That Decide Whether You Get Issued

A jurisdiction-aware 25-point checklist patent attorneys use the day before filing — covers USPTO, EPO, JPO, KIPO, and CNIPA formal requirements in one pass.

TL;DR

• The single highest-leverage moment in patent prosecution is 24 hours before filing — most formal rejections trace back to issues that this checklist catches in 30 minutes.
• The 25 items below are organized into 5 categories: line art, reference numerals, views & layout, jurisdiction-specific format, and metadata.
• A figure that passes all 25 items survives formal review in USPTO, EPO, JPO, KIPO, and CNIPA without rework.

Why a Checklist Matters More Than a Beautiful Drawing

Patent examiners do not score figures on artistic merit. They run a near-mechanical formal review: line weight, margins, view labels, numeral consistency, file format. A figure that fails any one of these triggers a notice of non-compliance and adds 2–6 weeks to the prosecution timeline — sometimes pushing the application past a priority deadline.

The checklist below is the same one experienced agents use the day before filing, condensed and made jurisdiction-aware so a single pass covers your major filings.

Category A — Line Art Quality (5 items)

1. All lines are black-and-white. No grayscale, no color, no JPEG compression artifacts. EPO Rule 46 and USPTO 37 CFR 1.84(b) both reject anything else.
2. Line weight is uniform and ≥ 0.3 mm for primary structural lines. Hairlines below this disappear when the office reduces the figure for publication.
3. Hatching is used only where required (cross-sections, distinguishing materials) and follows ISO 128-50 patterns. Decorative hatching is rejected.
4. No anti-aliased edges or gradients. A patent drawing must be clean line art. Anti-aliasing produces gray pixels that fail bitonal TIFF conversion.
5. No text inside line-art regions beyond reference numerals and standard labels (FIG. 1, A-A, etc.). Annotations like "switch on" or "transmit data" do not belong in figures.

Category B — Reference Numerals (6 items)

1. Every numeral in a figure appears in the written specification with the same designation. The most common formal rejection is "reference numeral X has no antecedent basis."
2. Every numeral in the specification appears in at least one figure. The reverse problem — described elements with no visual anchor — is equally fatal.
3. The same element gets the same numeral across all figures. A motor labeled 14 in Fig. 2 cannot be 18 in Fig. 5.
4. Different elements get different numerals. A numeral cannot ambiguously point to two distinct components.
5. Lead lines are straight, do not cross each other, and end on the element they identify — not adjacent to it.
6. Numeral fonts are sans-serif, ≥ 3.2 mm tall for utility filings. Smaller numerals fail microfilming and OCR.

Category C — Views & Layout (5 items)

1. Each figure is independently labeled (FIG. 1, FIG. 2A, FIG. 2B). Multiple drawings on one sheet require sub-labels.
2. View orientation is consistent. If Fig. 2 is a top view, the front-of-device convention must match Fig. 1's perspective.
3. Design patents include all 7 mandatory views (front, back, top, bottom, left, right, perspective) unless explicitly waived.
4. Cross-sectional views show hatching aligned with parent view. A section line in Fig. 1 (A-A) must produce a Fig. 2 with hatching that corresponds to the cut plane.
5. Page margins: USPTO 2.5 cm top / 1.5 cm sides; EPO 2.5 / 2.5 / 1.5 / 1.0 cm; JPO 2.0 cm minimum on all sides.

Category D — Jurisdiction-Specific Format (5 items)

1. USPTO: Bitonal TIFF, 300+ DPI, 21.6 × 27.9 cm sheet. PNG/JPG are not accepted for utility filings.
2. EPO: PDF/A-1b or PDF/A-2b, A4 sheet, no embedded images that exceed safe margins.
3. JPO (様式 26): A4, sheet number on top center, figure number above each figure as 「【図1】」 in Japanese.
4. KIPO: Korean figure caption 「도 1」 above each figure; same line-art and numeral rules as USPTO.
5. CNIPA: Black ink only, A4, figure number 「图 1」 below each figure (note: below, not above — opposite of JPO).

Category E — Metadata & File Hygiene (4 items)

1. Filename includes a sheet identifier (fig-01.tif, fig-02a.tif) for unambiguous matching to the specification.
2. Source file is preserved — keep the editable SVG in version control. If an examiner objection requires a small edit, you do not want to redraw.
3. No personally identifying metadata in the file (author, GPS, software watermarks). Most offices strip this on filing, but some leak it back through IFW publication.
4. All figures use the same coordinate origin if any cross-references locate elements by position. Inconsistent origins cause silent errors examiners catch six months later.

Pre-Filing Compliance Matrix

Checklist Category	USPTO	EPO	JPO	KIPO	CNIPA
Line art / B&W	✅	✅	✅	✅	✅
TIFF accepted	✅	❌ (PDF)	✅	✅	✅
Sheet size	Letter	A4	A4	A4	A4
Figure label position	Above	Above	Above 【図】	Above 도	Below 图
Min line weight	0.3 mm	0.32 mm	0.4 mm	0.3 mm	0.5 mm
Numeral height min	3.2 mm	0.32 cm	3.2 mm	3.2 mm	5 mm

How an Automated Figure Checker Replaces This Review

Walking through 25 items per figure × 6 figures × 5 jurisdictions = 750 manual checks per filing. This is why a built-in compliance checker is no longer optional in modern patent tooling. A good checker:

• Validates each item against the target jurisdiction's rule
• Flags numeral mismatches between figure and specification
• Auto-generates the per-jurisdiction format (TIFF for USPTO, PDF for EPO, A4 layout for JPO/KIPO/CNIPA)
• Returns a pass/fail report you can attach to the prosecution file as evidence of due diligence

FAQ

What is the most common formal rejection in patent figures?

Reference numeral inconsistency — either a numeral in the figure with no antecedent in the specification, or vice versa. This single category accounts for the majority of formal Office Actions in our experience.

Do design patents have a different checklist than utility patents?

Partially. Design patents add view-set requirements (all 7 views), broken-line conventions for unclaimed matter, and surface-shading rules. The line-art and numeral rules largely transfer.

Can I file the same TIFF to USPTO and EPO?

No. USPTO accepts TIFF; EPO requires PDF/A. Sheet sizes also differ (Letter vs A4). You need per-jurisdiction exports from the same source-of-truth figure.

How long does this checklist take to run manually?

For a typical 6-figure utility application, an experienced agent runs through this in 60–90 minutes. An automated compliance checker reduces it to under 5 minutes.

What's the cost of skipping this checklist?

A formal rejection adds 2–6 weeks. For a fast-moving market, that is often the difference between blocking a competitor and watching them publish first. For PCT national-phase entries, missing a deadline can permanently lose foreign rights.

Run the Checklist Automatically

Upload your figures and have all 25 items validated against your target jurisdictions: Open the PatentFig Figure Checker.