§9.5.2

Nested Tables

A table inside a cell—nest it, flatten it, or subdivide?

✅ NormativeSettled. The requirement holds as written.📄 Page ruleCan be applied from the page alone.Read §9.5.2 in the RFC ↗

The requirement

A small grid printed inside one cell of a table MUST be rendered by subdividing that cell into the outer table's own grid: the inner grid's cells become rows and columns of the outer table, and the neighbouring cells span them. The output MUST NOT contain a nested <table> element, and MUST NOT flatten the inner grid into text.

When it applies

A cell that itself contains a small grid: a fee schedule inside a plan-comparison cell, a mini-table of components inside one row of a summary.

Sketch of the printed page — layout, not output

| Plan | Fees                          |
| A    | ┌ admin │ 0.25% ┐            |
|      | └ fund  │ 0.10% ┘   ← a table inside the cell

Reading the examples. Each one pairs a source page with the output the rule expects. ✅ Sample: the rule applies. ❌ Counter-sample: it looks like it applies and does not, or a rendering got it wrong. A non-conforming output, in red, is shown only for contrast. … marks content left out of an excerpt.

Recognising a nested table

The inner grid has its own alignment: two or more columns of its own, sometimes its own header row, and its own row boundaries that do not line up with the outer table's rows. That is what separates it from a cell that merely holds several lines of text, which is governed by Record Groups and Multi-Line Cells (§9.5.3).

Rendering

The inner grid's cells MUST become real cells of the outer table, and every cell alongside it MUST span the rows it now occupies:

<tr>
  <td rowspan="2">A</td>
  <td>admin</td><td>0.25%</td>
</tr>
<tr>
  <td>fund</td><td>0.10%</td>
</tr>

A is printed once and genuinely covers both fee rows, so rowspan="2" is a true statement about the page — the same test Repeated Identical Values (§9.5.4) applies everywhere else.

No nested <table>. A nested table makes the inner grid invisible to anything that walks the outer one: cell counts, column arithmetic and per-cell boxes all stop at the <td> boundary. Subdividing keeps every value addressable at the same level as the rest of the table, and the outer grid still reconciles — see the leaf-track check in Multi-Row Header Tiers (§9.3.3).
Pairs MUST survive. The pairing inside the inner grid is the data: admin goes with 0.25% and fund with 0.10%. An encoding that lists all the labels and then all the values has destroyed the table; so has flattening the cell to <br/>-separated text.

This is one of several cases that need HTML tables rather than pipe tables, which cannot express the spans this rule depends on (see Markdown Rendering (§3.2)). The others are spans in Multi-Row Header Tiers (§9.3.3), full-width band rows in Bands Inside the Grid (§9.2.1), and level markers on the stub in Row-Label Hierarchy (§9.5.5).

✅ SampleThe rule applies

The left two columns form an embedded Section / Marks mini-table`en`

The left two columns form an embedded Section / Marks mini-table, with its own Summative Assessment II / 30% heading row, while a single ruled cell on the right spans all five of its rows and prints nothing. The TOTAL row is bold.

Source page

Expected output

Division of Syllabus for Term II (October-March)		Total Weightage Assigned
Summative Assessment II	30%
Section	Marks
Reading	20
Writing	20
Grammar	15
Literature	35
Formative Assessment		20%
TOTAL	90	50%

✅ SampleThe rule applies

A rowspan-6 단 원 별 교 육 내 용 stub encloses its own mini-grid`korean-curriculum`

A rowspan-6 단 원 별 교 육 내 용 stub encloses its own mini-grid — complete with a shaded header row 단원(제목) / 시수 / 교육내용 — inside the outer table. The shaded label cells on the left are bold; the two bulleted cells print • bullets.

Source page

Expected output

교 육 과 정	실무에 바로 쓰는 엑셀 입문: 보고서 & 데이터 정리
교 육 시 수	총 10시간	교 육 난 이 도	초중급
교육대상자	엑셀을 처음 접하거나 기초 지식이 부족하여 어려움을 겪는 분. 실무에서 바로 적용할 수 있는 엑셀 보고서 작성 및 데이터 정리 스킬이 필요한 분. 데이터 입력 시 오류를 줄이고 싶으신 분.
선 수 과 목		차 수 과 목	데이터, 엑셀로 똑똑하게 분석하기 (피벗 테이블 & 함수 활용)
교 육 목 표	보기 좋고 전문적인 실무 보고서 및 대장 양식을 만들 수 있습니다. 복잡한 데이터를 효율적으로 정리하고 원하는 정보를 추출할 수 있습니다. 데이터 정확성을 높이고, 간단한 계산 및 오류 처리를 할 수 있습니다.
단 원 별 교 육 내 용	단원(제목)	시수	교육내용
	엑셀 기본 익히기 및 데이터 입력 기초	1.5h	1. 엑셀 화면 구성과 효율적인 옵션 설정 2. 업무 시간을 줄이는 필수 단축키 3. 셀 편집 및 워크시트 관리 4. 데이터 입력 규칙과 효율적인 입력 방법
	서식과 표 꾸미기	1.5h	1. 셀 서식과 조건부 서식 활용 2. 표 스타일 지정 및 인쇄 영역 설정
	기초 함수 활용	2h	1. 합계·평균·개수 함수 2. 논리 함수(IF)의 기본 사용법
	데이터 정리와 필터링	2h	1. 정렬과 필터 2. 중복 데이터 제거
	실무 보고서 실습	3h	1. 주간 업무 보고서 양식 작성 2. 완성 파일 저장 및 공유 방법

Rule id tables-nested-tables · tables encoding rare

When it applies

Recognising a nested table

Rendering

Neighbouring rules, and how they differ

More