bitcastle LLC — Overseas Unregistered Crypto-Asset Exchange Targeting Japan
ConfidenceLikelyUpdated2026-07-29Review by2027-01-29Sources5Machine-translatedOriginal (JA)
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This entry sits under exchanges index. Read it with FSA crypto-asset exchange registration system — numbering, Local Finance Bureau jurisdiction, and registration requirements for adjacent context and Japan financial regulation — legal framework for tokens, crypto-assets, and payments for the broader system boundary.
No Japan FSA registration · Unregistered overseas-based operator · Warning notice issued 2024-11-28
1. Corporate Entity / Shareholders
- Trade name: bitcastle LLC
- Registered address: Euro House, Richmond Hill Road, Kingstown, St. Vincent and the Grenadines
- Established: 2019年 (initially founded in Singapore, later relocated to St. Vincent)
- Representative: Yoshimitsu Sekine (“Sekinemon”) — Japanese entrepreneur
- Parent company / Listing: Unlisted. A business entity of BLITZ GROUP (Mr. Sekine is CEO)
2. Licenses / Registration Status
- Japan FSA (Financial Services Agency) crypto-asset exchange registration: None
- St. Vincent and the Grenadines is a jurisdiction without a comprehensive licensing regime for crypto-asset exchange business. Registration with the FSA differs from a de facto license.
- JVCEA (Japan Virtual and Crypto assets Exchange Association): Non-member
- Registration under Japan’s Payment Services Act: None
3. Supported Currencies
- The FSA warning material is not a source for bitcastle LLC’s supported assets or product composition. This entry does not infer an asset count or availability to Japan residents.
4. Scope of Business
- The FSA warning material does not enumerate bitcastle LLC’s products, fees, leverage, or deposit and withdrawal functions. This entry is limited to the regulatory fact of unregistered operation on the warning date.
5. Market Share / Trading Volume
- The FSA warning material contains no comparable figures for bitcastle LLC’s Japan trading volume, account count, or market share. This entry does not infer market rank or scale.
6. History / Major Events
The table below is limited to the FSA’s primary source on crypto-asset exchange business in Japan. The warning letter does not establish the company’s incorporation year, corporate migration, or founder history, so those claims are not included. ^[Source: https://www.fsa.go.jp/policy/virtual_currency02/index.html.]
| Period | Event |
|---|---|
| 2024年11月28日 | FSA issued a warning notice: Under the Payment Services Act, named “Bitcastle LLC, representative Yoshimitsu Sekine” as a party conducting crypto-asset exchange business without registration. Issued simultaneously with KuCoin, Bybit Fintech Limited, MEXC Global, and Bitget Limited (a total of 5社). Basis: Crypto-Asset Exchange Operator Relations III-1-6 (2) ② |
Content of the warning: The FSA stated that the company conducted crypto-asset exchange business over the internet with Japan residents as counterparties. This entry does not infer nationality or uniqueness relative to the other warned operators when those points are not in the warning.
7. Strategic Developments
- The FSA issued its warning to bitcastle LLC on 2024-11-28. This entry does not use that material alone to infer subsequent Japan-facing service, product additions, or registration activity.
8. Related People
- Yoshimitsu Sekine: Named as the representative of bitcastle LLC in the FSA warning dated 2024-11-28.
Related
- japan-financial-regulation — Japan’s financial regulation overall
- jp-foreign-exchange-kucoin — KuCoin, which received a simultaneous warning
- jp-foreign-exchange-bybit — Bybit, which received a simultaneous warning (the 3th time)
- fsa-foreign-exchange-warning-system — FSA overseas-exchange warning framework
- jp-foreign-exchange-bitget — Bitget, which received a simultaneous warning
- jp-foreign-exchange-mexc — MEXC, which received a simultaneous warning
Sources
- A New Economy: FSA warns unregistered overseas crypto-asset exchanges (retrieved 2026-05-19)
- FSA bitcastle LLC warning notice PDF (issued 2024-11-28; URL currently returns 404; warning content confirmed via Google cache / snippet)
- FSA list of parties conducting financial instruments business without registration (retrieved 2026-05-19)
- Local Finance Bureau public notice on unregistered bitcastle LLC (published 2025-04-25)
- Kaigai FX Navi interview with bitcastle founder (retrieved 2026-05-19)
- Wikipedia ja — Bitcastle (requires cross-checking; not used alone for confidence assessment)
- coki.jp: Sekinemon (Yoshimitsu Sekine) (retrieved 2026-05-19; snippet confirmed)
Discovery
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