What Siena does

Siena Kobo (株式会社シエナ工房) is a Tokyo-headquartered Japanese IT services firm founded in June 2003 as a limited company and converted to a corporation in February 2005. As of April 2026, the company employs 25 people and operates from a single office in Chiyoda-ku, Tokyo, with ¥10 million in registered capital. The firm functions as a project-based professional services and on-site engineering staffing provider, delivering four interconnected service lines: business system development (requirements, design, development, testing), maintenance and operations support, legacy system modernization and migration, and technical/PMO support. Siena is distinctive in maintaining dual expertise across COBOL-based legacy systems and modern open systems (Java, C#, JavaScript, Python), enabling it to support phased modernization projects without fragmenting legacy maintenance from new development.

The company serves enterprise clients in telecommunications, finance, public sector, manufacturing, logistics, and — per its segment list — adjacent verticals, with named relationships including Fujitsu Limited (also a core implementation partner), T.S.E., Trust System, and Solxyz. The go-to-market is direct enterprise field sales: clients engage via the company's website inquiry form, phone (03-6206-8943), or in-person consultation, with engagement structured around project scoping and custom pricing rather than published rate cards. A worker dispatch license (Permit No. 派13-308936, obtained January 2018) permits on-site engineer placement at client locations, and JIPDEC Privacy Mark certification (most recently renewed July 2025) underwrites eligibility for personal-data-handling engagements in regulated sectors.

Siena is privately held with no disclosed institutional investors, no subsidiaries, no M&A activity, and no capital-raising history. Revenue is not publicly disclosed. Leadership has been stable since Nakamura Junji's appointment as Representative Director and President in March 2017, supported by a small board of directors and an auditor. The operating geography is single-country (Japan, Kanto region focus), with no documented international expansion. The company's revenue model is professional services on a project-contract basis, billed against scope, required expertise, and duration.

Name

Siena

Legal name

株式会社シエナ工房

Website

https://siena.jp

Company type

Private

Founded year

2003

Operating status

Operating

Headcount range

11–50 employees

Short description

Siena Kobo is a Tokyo-based Japanese IT services firm that provides business system development, maintenance, legacy modernization, and PMO support across COBOL and modern open-stack environments, serving enterprise clients in telecommunications, finance, and public-sector projects.

Ownership category

akta.pro rank

Product category

IT Services and System Development

NAICS

Computer Systems Design and Related Services (54151)

SIC

Services-Computer Integrated Systems Design (7373), Services-Computer Programming, Data Processing, Etc. (7370)

akta.pro primary industry

IT Program/Project Management (PMO) & Delivery Assurance (BPAEAAAO)

Keywords

• IT system development
• Legacy system migration
• Business application support
• PMO consulting services
• Enterprise software maintenance

Headquarters

HQ city

Tokyo

HQ country

Japan

HQ region

Asia

Offices1 record

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Technology or R&D, Operations, Marketing or Sales

Revenue model

1. IT Services and System Development: シエナ工房 generates revenue through project-based IT services including business system development, maintenance and operations support, legacy system modernization and migration, and technical/project management support. Services are provided on a project contract basis with both new development and existing system maintenance.

Pricing tiers

Go-to-market motion1 record

Distribution channels2 records

Marketing channels3 records

Core offering

株式会社シエナ工房 (Siena Kobo) is a Japanese IT services company that provides project-based business system development, maintenance and operations support, legacy system modernization and migration, and technical/project (PMO) support. Services span requirements definition, design, development, testing, migration, and ongoing maintenance across both COBOL-based legacy environments and modern open-system stacks (Java, C#, JavaScript, Python) for enterprise clients in telecommunications, finance, public sector, manufacturing, logistics, and healthcare.

Product overview

株式会社シエナ工房 (Siena Kobo) is an IT services company that provides a unified portfolio of business system services rather than a packaged software product. The company offers four core service offerings: 業務システム開発 (Business System Development), 保守・運用支援 (Maintenance and Operations Support), レガシー刷新・移行支援 (Legacy Modernization and Migration Support), and 技術支援/プロジェクト支援 (Technical and Project Support). These services work together to provide end-to-end support from requirements analysis through design, development, testing, migration, and ongoing maintenance. The company serves industries including telecommunications, finance, public sector, manufacturing, logistics, and healthcare, supporting both COBOL-based legacy systems and modern open systems using Java, C#, JavaScript, and Python.

Differentiator

Problem solved

Functional benefit

Quantifiable outcome

• Successfully supports large-scale core system modernization and integration projects with phased migration approaches
• +1 more outcomes

Named customers4 records

Segments6 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature1 record

Partnerships

One partnership is on record.

• 富士通株式会社 (Fujitsu Limited)coreImplementation/ SI/ Consulting PartnerMajor IT services company and key business partner. Provides enterprise system development and integration services as part of the IT services ecosystem. Representative major client listed in company materials.

Scale indicators3 records

Recent moves8 records

Expansion highlights4 records

Broad incumbents

• Fujitsu Limited: One of Japan's largest IT services companies and Siena's named major client and implementation partner; competes for the same enterprise modernization and integration work but at vastly greater scale and as a generalist.
• Otsuka Corporation: Major Japanese SI and packaged software reseller with strong SMB and enterprise system development practice; competes in some of Siena's mid-market and internal-system modernization opportunities.
• BIPROGY (formerly Nihon Unisys): Established Japanese SI with deep financial and public-sector system delivery heritage; competes for the same core system renewal and integration programs Siena targets via PMO and modernization work.
• Nomura Research Institute (NRI): Large Japanese consulting and SI firm with deep financial and public-sector core system expertise — overlaps with Siena in financial system renewal, PMO support, and legacy modernization engagements.
• SCSK Corporation: Large Japanese IT services company (Sumitomo group) covering system development, maintenance, and BPO — broad incumbent analog for Siena's enterprise system development and operations support services.
• TIS Inc. Major Japanese systems integrator offering business system development, maintenance, and IT outsourcing across finance, telecom, and public sector — the same verticals Siena serves, but with a much broader portfolio.

Emerging players

• Works Applications: Japanese enterprise software and consulting firm delivering large-scale core ERP and business system rollouts — adjacent to Siena in enterprise business system delivery, with a more product-centric model.
• BayCurrent Inc. Tokyo-based management and technology consulting firm whose strategy and digital practice includes systems design, PMO, and stakeholder coordination work that partially overlaps with Siena's PMO/調整 offering.

Direct peers

• ULS Group: Japanese IT consulting and systems integration boutique (formerly ウルシステムズ) specializing in end-to-end enterprise system delivery, PMO-style coordination, and legacy modernization — comparable in culture and offering to Siena but somewhat larger.
• Future Corporation: Tokyo-headquartered IT consulting firm whose core competency is large-scale legacy system modernization and open-system migration — directly overlapping Siena's stated COBOL-to-Java/Python modernization value proposition.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks1 record

Key highlights7 records

Customer concentration

Compliance1 record

Revenue estimate

Valuation estimate

Number of profiles

Profiles6 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Siena