Reissue Application Drawings: 7 Critical 37 CFR 1.173 Rules

A reissue is one of the few places in US practice where the drawings are governed by their own rule, and where ordinary amendment habits will get a filing bounced. Most practitioners know 35 U.S.C. 251 and the two-year broadening window. Far fewer know that reissue application drawings are controlled by 37 CFR 1.173, that the Office will not move the figures across from the original patent file, and that physically marking up a printed patent sheet is not an acceptable way to amend anything. The result is a predictable pattern of notices on otherwise competent reissue filings — all of them avoidable, none of them about the merits of the invention.

Rule 1: Reissue application drawings start with a clean copy of the printed patent

The starting obligation is set by 37 CFR 1.173(a)(2). The applicant must submit a clean copy of each drawing sheet of the printed patent at the time the reissue application is filed. If that copy complies with 37 CFR 1.84, the rule says plainly that no further drawings will be required.

Two consequences follow, and both catch people out. The first is that the Office will not transfer the drawings from the patent file to the reissue application. The reissue is treated as a fresh application file that happens to be about an existing patent; nothing arrives in it automatically. A reissue filed without drawing sheets is incomplete even though the figures are sitting in the parent file a few clicks away.

The second is the quality standard. MPEP 1413 glosses “clean copy” as good-quality photocopies free of any extraneous markings. In practice that means no annotations, no highlighter, no handwritten figure numbers, and no scanner artefacts along the gutter. The printed patent is typically reduced from the original sheets, so a copy made from the published document can fall below the line-quality and character-height thresholds of 37 CFR 1.84 even when it looks acceptable on screen. Where that happens, new formal sheets are the cheaper route than arguing about legibility.

• File a clean copy of every drawing sheet, not only the sheets you intend to change.
• Strip every extraneous marking — the rule is about markings, not about intent.
• Test the copy against 37 CFR 1.84 for line density and character height before filing.
• Assume nothing crosses over from the original patent file.

Rule 2: Never alter the original or printed patent drawing sheets

This is the single most common procedural error in reissue drawing practice, and MPEP 1413 states the prohibition flatly: amending the original or printed patent drawing sheets by physically changing or altering them is not permitted.

The instinct comes from older amendment practice, where red ink on a sheet was how a change was proposed. That mechanism is gone. Reissue application drawings are amended by substitution rather than annotation, so in a reissue there is no such thing as a marked-up sheet that is the amendment. Any change to a figure is made by substituting a whole sheet, and a marked-up copy — if you file one at all — is an explanatory exhibit, not the operative document. Conflating the two produces a filing where the Office cannot tell what the drawing of record is supposed to be.

The same discipline applies in ordinary prosecution, which is why the mechanics are worth learning once and reusing. Our guide to amending patent drawings covers the replacement-sheet workflow in a pending application; the reissue version is stricter only because the baseline document is a printed patent rather than a pending specification.

Rule 3: A replacement sheet must carry every figure that was on the sheet

Under 37 CFR 1.173(b)(3), any change to the patent drawings must be submitted as a replacement sheet of drawings, attached to the amendment document. The replacement sheet must comply with 37 CFR 1.84, and — this is the part that drives the drafting cost — it shall include all of the figures appearing on the original version of the sheet, even if only one figure is amended.

So a sheet carrying FIG. 3, FIG. 4 and FIG. 5 cannot be replaced with a sheet carrying only a corrected FIG. 4. All three figures come back, two of them unchanged, on a sheet that now has to satisfy 37 CFR 1.84 in its own right. When the surviving figures were only ever available as a reduced printed-patent image, they have to be redrawn to formal standard to travel on the new sheet. That is frequently the hidden cost in a reissue drawing budget, and it scales with how densely the original sheets were packed rather than with how many figures you actually want to change.

It also argues for a specific sequencing decision. Identify every figure you may want to touch before anyone starts drafting, because the marginal cost of a second change on a sheet you are already replacing is close to zero, while the marginal cost of a change on a fresh sheet is a whole sheet. Reissue application drawings reward batching in a way that pending-case amendments do not.

Rules 4 and 5: The labels — Amended, New, Canceled, New Sheet

37 CFR 1.173(b)(3) prescribes an exact vocabulary, and the examiner reads it as a control system rather than as housekeeping:

• Amended — any figure that has been changed must be identified as “Amended”.
• New — any added figure must be identified as “New”.
• Canceled — a canceled figure must be surrounded by brackets and identified as “Canceled”. Note that it is not simply deleted; the bracketed placeholder is how the record shows the figure was removed deliberately.
• New Sheet — any new sheet of drawings containing an additional figure must be labeled in the top margin as “New Sheet”.

The bracketing convention for canceled figures mirrors the bracketing used for deleted text in reissue specification amendments under 37 CFR 1.173(d), where matter to be omitted is enclosed in brackets and added matter is underlined. Reissue is a record-of-changes procedure throughout: the file is supposed to show, on its face, every difference between the original patent and the reissued one. A figure that silently disappears defeats that purpose, which is why the rule asks for a bracketed, labelled absence instead.

Labelling is the cheapest part of reissue application drawings to get right and one of the most common things to get wrong. Get it wrong and the consequence is rarely substantive — it is a notice, a response, and weeks of pendency on a patent that is usually being reissued because someone needs it fixed quickly.

Rule 6: Annotated Marked-up Drawings and the detailed explanation

There is a place for a marked-up figure in reissue application drawings, and it is tightly defined. A marked-up copy of an amended figure, carrying annotations that indicate the changes made, may be included — it is optional unless the examiner requires it in an Office action. Where one is filed it must be clearly labeled “Annotated Marked-up Drawings” and presented in the amendment or remarks section that explains the change.

The mandatory half is the narrative. All changes to the drawings must be explained, in detail, beginning on a separate sheet accompanying the papers that include the drawing amendment. “FIG. 4 amended” is not an explanation. What the examiner needs is the element, the change, and — critically — the support: where in the original disclosure the amended content was already taught.

That last element is what turns the explanation from a formality into the document that protects the amendment, for the reason set out next.

Rule 7: A new figure can be new matter under 35 U.S.C. 251

35 U.S.C. 251 contains a sentence that governs every drawing decision in a reissue: “No new matter shall be introduced into the application for reissue.” The rule permits an added figure and tells you to label it “New”. The statute decides whether that figure is allowable, and the two questions are independent.

The distinction that matters is between illustrating what the original disclosure already taught and adding content it did not. Redrawing an existing view to formal standard, correcting a reference numeral to match the description, or breaking a crowded figure into two views is presentation.

Adding a dimension that was never disclosed, a structural detail visible nowhere in the original figures or text, or a variant developed after the patent issued is new matter — and it does not become acceptable because it arrives as a drawing rather than as text. Figures are part of the disclosure, which is the same principle that makes them citable against others; our note on patent drawings as prior art covers the other direction of that rule.

There is a timing constraint sitting alongside it. 35 U.S.C. 251 also provides that no reissued patent shall be granted enlarging the scope of the claims of the original patent unless applied for within two years from the grant of the original patent. Where a new figure is being added to support broader claims, the drawing work and the two-year window are the same deadline, and the figure set needs to be ready well before the end of it.

Practical consequence: write the detailed explanation required by Rule 6 as a support map. For each change, cite the column and line of the original patent, or the original figure, that already disclosed it. An examiner who can see the support in the explanation has little reason to raise new matter at all, and it is the single most useful document in a set of reissue application drawings.

Design reissue drawings are governed by 37 CFR 1.152

A design reissue runs on the same 37 CFR 1.173 machinery as utility reissue application drawings, but the sheets themselves answer to 37 CFR 1.152 rather than to the utility standards of 37 CFR 1.84. That is a meaningful difference, because in a design patent the drawing is effectively the claim. Changing a figure changes the claimed design, so the no-new-matter analysis bites far harder than it does on a utility figure.

The broken-line convention is where this concentrates. Converting a solid line to a broken line removes that feature from the claimed design and broadens it; doing the reverse narrows it. Either way it is a claim amendment performed with a pen, and a broadening change brings the two-year bar of 35 U.S.C. 251 into play. Our guides to design patent drawing broken lines and to the 37 CFR 1.84 requirements set out the two standards side by side.

Europe has no reissue — and Rule 46 EPC no longer exists

Practitioners preparing reissue application drawings for a parallel European family sometimes look for the EPO equivalent of a reissue. There is not one. A granted European patent is changed centrally either through limitation or revocation proceedings under Article 105a EPC, which can only narrow the patent, or through opposition. There is no European procedure for broadening a granted patent after the fact, so the US two-year reissue window has no counterpart to plan around.

If a provider quotes you “Rule 46 EPC compliance” for the replacement sheets, the citation is stale. Rule 46 EPC was deleted with effect from 1 February 2023, along with Rule 49(3) to (12) EPC; the drawing presentation requirements moved into a Decision of the President published in the Official Journal so the Office can adjust them without amending the Implementing Regulations. The working text to cite today is the EPO Guidelines for Examination, Part A, Chapter IX. Our guide to EPO Guidelines A-IX covers what changed.

Reissue or certificate of correction? Pick the cheaper instrument

Not every drawing defect needs a reissue, and filing one when a certificate of correction would do is an expensive way to fix a typo. The dividing line is roughly whether the error affects the disclosure or merely the printed document.

• Certificate of correction — suits a Office-introduced printing error, or an applicant’s minor mistake of a clerical or typographical character that does not require re-examination, such as a figure printed upside down or a reference numeral mis-set in printing.
• Reissue — needed where the figures have to change in a way that bears on what the patent discloses or claims: a missing view a claim depends on, a figure that contradicts the description, or any design-patent line change.
• Neither — where the real problem is claim scope rather than illustration, a continuation filed while the family was still pending was the better instrument; see continuation application drawings.

Our reissue patent guide and certificate of correction guide walk through the choice in more detail. The drawing question is often what decides it, which is a good argument for having the figures reviewed before the instrument is chosen rather than after.

The seven checks, in filing order

1. File a clean copy of every printed drawing sheet with the reissue, free of extraneous markings, and confirm it meets 37 CFR 1.84 — nothing transfers from the patent file.
2. Do not physically alter an original or printed patent sheet. Changes travel on replacement sheets only.
3. Build each replacement sheet with every figure that appeared on the original version of that sheet, redrawn to formal standard where necessary.
4. Label precisely: “Amended”, “New”, bracketed “Canceled”, and “New Sheet” in the top margin of any added sheet.
5. Explain all changes in detail, beginning on a separate sheet; add “Annotated Marked-up Drawings” only as a clearly labelled exhibit.
6. Test every added or altered figure against the no-new-matter bar of 35 U.S.C. 251, and cite the original support in the explanation.
7. For a design reissue, apply 37 CFR 1.152 and treat any solid-to-broken line change as a claim amendment subject to the two-year broadening bar.

None of these are judgement calls. They are the published mechanics of 37 CFR 1.173 and MPEP 1413, and reissue application drawings that follow them keep the file’s pendency on the merits where it belongs.

Get Reissue-Ready Replacement Sheets

PerspireIP prepares reissue application drawings and replacement sheets from printed patent copies, original CAD or legacy paper figures — every figure on the sheet redrawn to 37 CFR 1.84 or 37 CFR 1.152 standard, labelled to 37 CFR 1.173(b)(3), with a change explanation that maps each amendment to its support in the original disclosure. See our patent drawing services or contact us with the patent number and the figures you need changed. Every set ships with a written copyright assignment.

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