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Custody Bank of Japan operating model

ConfidenceLikelyUpdated2026-07-29Review by2026-10-27Sources14Machine-translatedOriginal (JA)

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This entry sits under banking index. Read it with the entity anchor Custody Bank of Japan (CBJ), the operating peer Master Trust Bank operating model and entity MTBJ, the landscape summary Japan master trust and custody bank landscape, the cross-camp matrix Japan trust bank vs global custodian comparison matrix, and the operating comparison trust-bank custody operating comparison. Pair it with JASDEC and JSCC for the settlement-infrastructure side, with Japan banking license tier comparison matrix for the regulatory tier, with the shareholder-side trust-bank pages SMTB and Mizuho Trust, and with Japan listed financial groups investable universe for the institutional context.

TL;DR

Custody Bank of Japan (CBJ — 日本カストディ銀行) is an asset-administration bank created in July 2020 through the merger of JTC Holdings, Japan Trustee Services Bank, and Trust & Custody Services Bank. CBJ’s current company profile lists Sumitomo Mitsui Trust Group (33.3%), Mizuho FG (27.0%), Resona Bank (16.7%), Dai-ichi Life (8.0%), and four other life insurers as shareholders; its recruiting disclosure describes more than JPY 710tn of assets under custody as of 2025-09. The FSA bank workbook lists CBJ in the trust-bank category, while CBJ’s own business pages describe custody, settlement, accounting, reporting, securities lending, and institutional outsourcing. These sources support CBJ’s scale and role, but do not by themselves establish that CBJ plus MTBJ hold a quantified majority of all Japanese institutional-custody volume, so this page does not present that comparison as a measured fact. ^[Sources: https://www.custody.jp/corporate/information/index.html; https://www.custody.jp/recruit/aboutus/about.html; https://www.custody.jp/recruit/aboutus/business.html; https://www.fsa.go.jp/menkyo/menkyoj/ginkou.xlsx.]

1. 機関位置

Field CBJ
Legal name (JA) 株式会社日本カストディ銀行
Legal name (EN) Custody Bank of Japan, Ltd.
Established 2020-07-27 (JTSB + TCSB merger)
HQ 東京都中央区晴海 1-8-12 晴海アイランドトリトンスクエア オフィスタワー Z
License route 銀行法 + 信託業法 (custody-only 信託銀行 / 信託兼営銀行)
Listing Non-listed (multi-FG joint venture)
Primary regulator 金融庁 (FSA)
Industry body 信託協会 (Trust Companies Association of Japan)
Functional position Asset-administration specialist (no loans, no PB, no real-estate trust, no inheritance trust)
Public AUC anchor Approximately ¥696 trillion total assets under custody (受託信託財産 + 常任代理契約等に基づく預り資産; of which 信託財産 ¥476tn) as of 2025-03-31
Peer Master Trust Bank of Japan (MTBJ)

Sources: ^[CBJ company information, https://www.custody.jp/corporate/information/index.html; CBJ 2025 disclosure, https://www.custody.jp/data/disclosure/pdf/disclosure202507.pdf; FSA licensed-bank register, https://www.fsa.go.jp/menkyo/menkyoj/ginkou.xlsx.]

Shareholder structure (public disclosure, as of 2020-07-27)

Shareholder Stake Reading
Sumitomo Mitsui Trust Group (SuMi TRUST) 33.3% Shareholder listed by CBJ
Mizuho FG (Mizuho FG) 27.0% Shareholder listed by CBJ
りそな銀行 (Resona Bank) 16.7% Shareholder listed by CBJ
Daiichi Life Group / formerly Dai-ichi Life HD 8.0% Shareholder listed by CBJ
朝日生命保険 5.0% Shareholder listed by CBJ
明治安田生命保険 4.5% Life-insurer shareholder
かんぽ生命保険 3.5% Life-insurer shareholder
富国生命保険 2.0% Life-insurer shareholder

Sources: ^[CBJ company information, https://www.custody.jp/corporate/information/index.html. Shareholding does not by itself prove the source or allocation of customer mandates.]

Why two specialist custodians, not one

The official merger materials establish the 2020 combination that created CBJ. The reviewed public sources do not state why CBJ and MTBJ remain separate, so shareholder politics, risk concentration, and future consolidation should not be presented as company-confirmed explanations.

Lineage diagram

SMTB / 第一生命 lineage
  日本トラスティ・サービス信託銀行 (JTSB) — 2000 設立
    ├── 旧中央三井信託 → SMTB
    ├── 旧住友信託 → SMTB
    └── 第一生命

Mizuho / Resona / 生保 lineage
  資産管理サービス信託銀行 (TCSB) — 2004 設立
    ├── みずほ信託 (Mizuho Trust)
    ├── りそな銀行 (旧 大和 / あさひ信託 系統)
    ├── Asahi Life, Meiji Yasuda, Japan Post Insurance, Fukoku Life
    └── 旧第一勧業富士 / 安田信託 系統

  ↓ 2020-07-27 merger

  日本カストディ銀行 (CBJ) — 株主 (2020-07-27 現在)
    ├── 三井住友トラストグループ (SMTH) 33.3%
    ├── みずほ FG (Mizuho FG) 27.0%
    ├── りそな銀行 (Resona) 16.7%
    ├── 第一生命 8.0%
    └── 朝日生命 5.0% / 明治安田 4.5% / かんぽ生命 3.5% / 富国生命 2.0%

Business-line map

Segment Core function Typical client base What it is not
信託カストディ (Securities custody) Safekeeping of equities, JGB, corporate bonds, foreign securities; book-entry registration; corporate-actions processing; dividend / interest receipt; tax reclaim ops Pension plans, asset managers, life insurers, foreign global custodians needing a Japan sub-custodian Not a proprietary investor; 「信託口」 nominee label is a recordkeeping construct
年金信託 (Pension trust administration) Trust contract administration, recordkeeping, reporting, and benefit-payment operations Pension plans and their appointed service providers Not the investment manager
投信受託 (Securities-investment-trust admin) Fund accounting, NAV calculation, holdings records, and distribution processing under the trust contract Asset managers that appoint CBJ as trustee Not the fund manager or distributor
特定金銭信託 (特金) ops 特金 vehicles for institutional / corporate investors Insurers, corporates, regional banks Not a discretionary asset manager
資産管理サービス (Master custody) Institutional master-custody, multi-mandate consolidation, investment-instruction processing Large multi-mandate asset owners Not the sponsor

Sources: ^[CBJ business overview, https://www.custody.jp/recruit/aboutus/business.html. The page describes service categories; it does not publish a customer-by-customer mandate list.]

Operating-function breakdown

Function Description
Safekeeping & book-entry admin Direct connection to JASDEC book-entry transfer; BoJ JGB direct-account holder; cash-settlement-account operation
Settlement (cash equity) DVP-X1 / DVP-X2 / DVP-X3 settlement via JASDEC + JSCC clearing
Settlement (JGB) Direct participation in BoJ JGB book-entry system
Settlement (corporate bond / CP) Book-entry transfer via JASDEC for 社債 and CP
Fund accounting / NAV calculation Daily NAV calculation for 投信 mandates; 投信協会 standards
Corporate actions Dividend / interest receipt, splits, rights offerings, conversions; foreign-asset CA via global custodian sub-network
Voting operations Mechanical execution of asset-owner / manager instructions; ICJ electronic-voting forwarding
Sub-custody for foreign assets Re-routing via BNY Mellon / State Street / JP Morgan / Citi for non-JP assets
Member / participant ops Pension member balance reporting (DB / DC), benefit-payment ops
Securities-lending support Lending program admin (when client opts in); collateral posting; recall management

The 「信託口」 nominee surface — CBJ specific

CBJ’s nominee name 「日本カストディ銀行（信託口）」 appears in the top-shareholder rows of substantially every TOPIX-100 issuer, often as 2nd or 3rd after MTBJ’s 「信託口」. The pattern is:

Reading Interpretation
Legal record name CBJ
Beneficial owners Not identifiable from the nominee row alone; the holding is administered for underlying trust beneficiaries or customers
Voting instruction source Determined by the applicable trust / investment-management arrangement; the shareholder register alone does not identify it
Underlying exposure type Not identifiable from the nominee row alone

Sources: ^[CBJ business overview, https://www.custody.jp/recruit/aboutus/business.html; issuer shareholder registers identify the nominee but generally do not disclose the underlying mandate.]

vs MTBJ — operating-detail comparison

Field CBJ MTBJ
Established 2020-07-27 (JTSB+TCSB merger) 2000-05 (greenfield)
Shareholder camp SMTH 33.3% + Mizuho FG 27.0% + Resona 16.7% + 第一生命 8.0% + 朝日 / 明治安田 / かんぽ / 富国 生保 MUFG Trust + Nippon Life + Meiji Yasuda + Norinchukin
Lead shareholder stake 三井住友トラストグループ (SMTH) 33.3% MUFG Trust 46.5%
Public AUC anchor ~¥696tn (2025-03-31; total assets under custody) ~¥770tn (2025-03-31; 管理資産残高)
HQ location 東京都中央区晴海 東京都港区浜松町
Legal-structure license 銀行法 + 信託業法 (custody-only) 銀行法 + 信託業法 (custody-only)
Published business focus Asset administration and custody Asset administration and custody
Retail / PB / real-estate services Not presented as a business line on the reviewed official overview Not presented as a business line on the reviewed official overview
Infrastructure participation Verify in the current participant lists of JASDEC, JSCC, and BoJ Verify in the current participant lists of JASDEC, JSCC, and BoJ
Named customer mandates Not comprehensively disclosed Not comprehensively disclosed
Listing Non-listed Non-listed

Sources: ^[CBJ company information and disclosure, https://www.custody.jp/corporate/information/index.html; MTBJ company information and FY2024 results, https://www.mastertrust.co.jp/about/overview.html, https://www.mastertrust.co.jp/assets/pdf/financial/zm20250521.pdf.]

vs full-service trust banks

Dimension CBJ Megabank full-service trust banks (MUFG Trust / SMTB / Mizuho Trust)
Custody / 投信受託 Officially described core service Full-service banks publish their own trust and custody services; delegation must be evidenced mandate by mandate
Real-estate trust No Major business line (RE securitization, J-REIT)
相続 / 遺言 / PB No Yes — significant wealth-management revenue
不動産信託 + 信託受益権 (J-REIT) No Yes — full processing
Securities agency (株式事務代行) No Yes
Pension front-office (運用提案) No Yes
DC service window Confirm from CBJ’s current service description Confirm from each bank’s current service description

Sources: ^[CBJ business overview, https://www.custody.jp/recruit/aboutus/business.html; Trust Companies Association of Japan member and service information, https://www.shintaku-kyokai.or.jp/trust/trustbanks/.]

CBJ’s public materials describe asset-administration processing. They do not establish a universal front-office / back-office allocation for every shareholder customer or explain the shareholders’ consolidation decisions.

vs global custodians

Dimension CBJ Global custodians (BNY Mellon / State Street / JPM / Citi Japan)
Public business description Japan-based asset administration and custody Parent groups publish global securities-services networks
Japan-specific AUC / revenue Entity disclosure where published Often not separately disclosed from parent totals
ICSD / market connectivity Verify through current entity and infrastructure disclosures Verify through current entity and infrastructure disclosures
Mandate pricing Not published as a general tariff Not published as a Japan-unit general tariff
Regulatory base Japanese entity is subject to applicable Japanese supervision Japanese entity plus applicable home-country group supervision

Sources: •

4. 手数料・収益構造

CBJ does not publicly disclose detailed fee schedules. The public-domain reading is:

Revenue line Pricing basis Public visibility
Pension trust administration Contract-specific; no entity-wide public rate established Not disclosed at line-item level
投信受託 administration Fund-specific remuneration can be checked in each fund’s statutory documents Observable fund by fund, not as a CBJ-wide rate
Securities custody Contract-specific No general public tariff identified
Voting / corporate actions Contract treatment not established by the reviewed public material Not separately disclosed
Securities lending Contract treatment not established by the reviewed public material Not separately disclosed
Own-account interest income Reported only through the bank’s financial statements No mandate-level attribution

Sources: ^[CBJ disclosure publications, https://www.custody.jp/data/; individual fund prospectuses and trust deeds for fund-specific trustee remuneration.]

Why CBJ fee economics resemble MTBJ closely

Both run the same product set against similar mandate scales. Their fee pricing is anchored by:

  1. GPIF tender pressure — GPIF runs periodic 資産管理機関 panels where CBJ and MTBJ both compete; both incumbent-priced and challenger-priced.
  2. Passive-fund AUM growth — passive index funds have driven up CBJ-administered AUC while pushing down per-bp fees, producing volume-up / margin-down dynamics.

Cross-bank fee-economy reading

For granular MTBJ + CBJ + megabank trust-arm + global-custodian fee comparison see trust bank fee structure comparison.

Aspect CBJ MTBJ
Public mandate tariff Not disclosed Not disclosed
Fund-specific trustee remuneration Check each fund’s statutory documents Check each fund’s statutory documents
Entity financial result CBJ statutory disclosure MTBJ statutory disclosure
Valid public comparison Business scope, disclosed AUC definition, and reporting perimeter Business scope, disclosed AUC definition, and reporting perimeter

Sources: •

Regulatory stack

Layer Statute / regulator CBJ implication
Bank supervision 銀行法 + 金融庁 監督指針 (信託兼営銀行 section) Capital adequacy + governance + IT-risk; CBJ runs a light credit book and consequently a light capital ratio relative to AUC
Trust-business supervision 信託業法 + 金融庁 監督指針 (信託業 section) Trust account separation, fiduciary duty, conflict-of-interest controls
Securities-law overlay 金融商品取引法 — 投信受託会社 / カストディ ops NAV calc, custody standards, 投信協会 compliance
Pension regulation 厚生年金保険法, 確定給付企業年金法, 確定拠出年金法 DB / DC administration, fiduciary reporting
Deposit insurance 預金保険機構加盟 Statutory membership; minor relevance given small deposit base
AML / CFT 金融庁 + 警察庁 + 国税庁 reporting Custody-side AML applied at underlying client level
Stewardship / governance スチュワードシップ・コード (voluntary) Voting-admin transparency; CBJ executes per client instruction
Data / personal info 個人情報保護法, 金融分野ガイドライン Pension member data, NISA data

Sources: ^[FSA trust-business financial-institution list, https://www.fsa.go.jp/menkyo/menkyoj/kenei.pdf; FSA bank supervisory guidance, https://www.fsa.go.jp/common/law/guide/city/.]

Accounting treatment

Item Treatment
Trust assets (信託財産) Off-balance-sheet at CBJ; on-balance at beneficial owner
Custody / admin fees Recognized as fee income in P&L
Own-account deposits On-balance-sheet — small
Settlement-account residuals Short-duration; cash + due-from-banks
Goodwill / merger accounting (2020) Recognized on JTSB + TCSB merger; specifics in shareholder consolidated disclosure

Sources: ^[CBJ 2020 and 2021 disclosure publications, https://www.custody.jp/data/disclosure/pdf/_disclosure2020.pdf, https://www.custody.jp/data/disclosure/pdf/_disclosure202101.pdf.]

Merger-accounting note

CBJ’s 2020 annual and interim disclosures confirm the three-company merger and publish aggregate balance-sheet and income information after launch. The reviewed public CBJ disclosures do not provide a standalone schedule attributing multi-year system-integration costs, IT write-downs, or goodwill recovery to individual shareholder-parent segments. Those allocations should therefore be treated as undisclosed rather than inferred from the merger itself. ^[Sources: https://www.custody.jp/data/disclosure/pdf/_disclosure2020.pdf; https://www.custody.jp/data/disclosure/pdf/_disclosure202101.pdf.]

6. JASDEC / clearing infrastructure connection

┌─────────────────────────────────────────────────────────────────┐
│ Beneficial owners (GPIF / corporate pensions / 投信 / insurers)  │
└─────────────────────────────┬───────────────────────────────────┘
                              │  mandate
                              ▼
┌─────────────────────────────────────────────────────────────────┐
│ Asset managers (front-office discretion + voting opinion)        │
│ — SMTB AM affiliates, Mizuho AM, Resona AM, etc.                 │
└─────────────────────────────┬───────────────────────────────────┘
                              │  instruction
                              ▼
┌─────────────────────────────────────────────────────────────────┐
│ Custody Bank of Japan (trust account / nominee)                  │
│ — recordkeeping, NAV, CA processing, voting admin                │
└─┬────────────┬────────────┬───────────────┬────────────────────┬─┘
  │            │            │               │                    │
  ▼            ▼            ▼               ▼                    ▼
┌───────────┐┌─────────────┐┌──────────────┐┌──────────────────┐┌─────────────────┐
│ JASDEC    ││ JSCC        ││ BoJ JGB      ││ Global custodians│ │ ICJ voting plat.│
│ (equities,││ (CCP for    ││ book-entry   ││ for foreign sub- │ │ (electronic     │
│ 社債, CP, ││ cash equity)││ (JGB         ││ custody          │ │ proxy voting)   │
│ 投信)     ││             ││ settlement)  ││                  │ │                 │
└───────────┘└─────────────┘└──────────────┘└──────────────────┘└─────────────────┘

Direct JASDEC participation

CBJ is a direct participant in:

  • 株式振替制度 (dematerialized listed shares)
  • 一般債振替制度 (corporate bonds: 普通社債, 転換社債)
  • 短期社債振替制度 (CP)
  • 投資信託振替制度 (publicly offered 投信 units)

JSCC + DVP

CBJ’s cash-equity settlement runs through JSCC as the central counterparty, producing DVP-X1 / X2 / X3 quality settlement. JSCC also runs CCP services for repos and OTC derivatives — CBJ’s exposure to these layers depends on individual client mandate scope.

BoJ JGB book-entry

CBJ holds a direct account in the BoJ JGB book-entry system, supporting DVP JGB settlement for pension and 投信 mandates without intermediate sub-custody.

Foreign-asset sub-custody chain

For non-JP assets in CBJ-administered mandates:

CBJ (record-name trust-account)
  → Global custodian (BNY / State Street / JPM / Citi)
    → Local sub-custodian in foreign market
      → Local CSD

Sources

  • Custody Bank of Japan: official site, about us, business explanation, corporate information page, English corporate page.
  • 三井住友信託銀行「スケールメリットの追求」資産管理業務ページ（CBJ AUC: 総預かり資産 約696兆円 / 信託財産 476兆円、2025-03-31）— https://www.smtb.jp/business/instrument/management/scale
  • 日本マスタートラスト信託銀行 2024 年度決算（MTBJ 管理資産残高 約770兆円、2025-03-31）— https://www.mastertrust.co.jp/assets/pdf/financial/zm20250521.pdf
  • Trust Companies Association of Japan: trust-assets-under-management statistics.
  • FSA: trust-business financial institution list, bank license list.
  • JASDEC: securities book-entry and depository system materials.
  • JSCC: clearing and DVP cash-equity materials.
  • BoJ: JGB book-entry settlement system materials.
#banking#trust-bank#custody#asset-administration#pension#settlement-infrastructure

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