[Summary]
What attracted attention in the news of the arrest of the former MTU representative was not only the amount of damage caused. Another point of contention was that the investor was J-STAR, a PE fund that invests in Japanese mid-sized and small-to-medium-sized companies.
J-STAR is described on its official website as a private equity investment company that works to solve problems for small and medium-sized companies in Japan, and began investment activities in 2006, with a cumulative track record of over 100 investments.
In this article, rather than criticize J-STAR individually, we will use the MTU incident as an opportunity to summarize the profit structure of PE funds, hands-on support, the strengths of Japanese-style PE, and the difficulties of due diligence for intangible asset businesses such as AI, SaaS, and medical DX.
First, the conclusion
What the MTU incident showed us is not simply that even professionals make mistakes.
What is more important is that there is a difference in the degree of difficulty in verifying the existence of intangible asset-based businesses such as AI, SaaS, and medical DX.
| Issues | Points to watch |
|---|---|
| J-STAR's position | PE fund for small and medium-sized enterprises in Japan |
| PE profit structure | Increasing corporate value after acquisition and aiming for profit from sale |
| Strengths of Japanese PE | Business succession, carve-outs, industry reorganization, business management improvement |
| Issues in the MTU case | How to confirm sales, customers, and product reality |
| Future challenges | Importance of technical DD, SaaS analysis, and data audit |
The MTU incident is currently at the arrest and suspicion stage, and the final determination of facts will be left to future judicial proceedings.
However, from the perspective of investment practice, this is a case that forces PE funds to redesign the DD when acquiring digital companies.
Who is J-STAR?
J-STAR is a Japanese private equity investment company.
The official website describes the company as a company that works to solve the problems of mid-sized and small-to-medium-sized businesses in Japan through investment.
The company started investment activities in 2006, and on its official website it states that it has made more than 10 investments every year in the last five years, and has a cumulative investment record of more than 100 investments.
In addition, in order to maximize the business value of investee companies, we are committed to building and implementing business strategies together with the managers of investee companies.
In other words, J-STAR is not an investor who simply buys stocks and waits for the price to rise.
They are a type of PE player who enters into companies and increases value through management improvement and growth support.
What is a PE fund?
A PE fund is an investment fund that primarily invests in unlisted companies and businesses and aims to generate returns by increasing corporate value and then selling the funds.
The characteristics are different from listed stock investment and VC investment.
| Item | VC | PE Fund |
|---|---|---|
| Main targets | Start-ups, early growth companies | Small and medium-sized enterprises, mature companies, business sectors |
| Investment ratio | Many minority stakes | Many majority acquisitions and management rights |
| Success model | Aiming for a major IPO or acquisition | Aiming for profit from sale after management improvement |
| Level of involvement | Support is available but management rights are often limited | Easy to be deeply involved in management |
| Period | Varies depending on the project | Tends to be several years |
VC tends to follow a model in which the overall return of the fund is generated by the great success of a few of the many investments.
On the other hand, PE funds aim to become deeply involved in management after an acquisition and reshape corporate value itself.
J-STAR investment model
J-STAR's official website states that its investment criteria include that J-STAR's involvement adds value and emphasizes the uniqueness and superiority of its business model.
Regarding the investment size, it is explained that the equity investment amount is approximately 1 billion yen to 3 billion yen as a guide, and will vary depending on the project.
The holding period is generally 3 to 7 years, and exit strategies include sale to a business company, MBO, and IPO.
To summarize, J-STAR's investment model is as follows.
| Item | Contents |
|---|---|
| Characteristics of funds | Managing fund funds collected from investors |
| Investment targets | Japanese medium-sized and small businesses, businesses with room for growth |
| Investment size | Estimated equity investment of 1 billion yen to 3 billion yen |
| Holding period | Approximately 3 to 7 years |
| Value improvement | Business management, growth strategy, M&A, industry reorganization, etc. |
| Collection method | Sale of business company, MBO, IPO, etc. |
In this model, what is important is not only the price at the time of investment, but also how much the company can be changed after the acquisition.
What is value up?
The core idea of PE funds is to increase value.
This means improving the acquired company's profitability, growth potential, management structure, and business portfolio, and increasing its corporate value.
Corporate value can be simplified as follows.
Key point= EBITDA × Key pointEBITDA is a measure of profitability excluding the effects of interest payments, taxes, depreciation, etc.
PE funds aim to increase EBITDA, increase valuation multiples, or both.
| Improvement methods | Impact on corporate value |
|---|---|
| Sales growth | Easily increases EBITDA |
| Improve profit margin | Increase profitability even with the same sales |
| Strengthening the management system | Increasing reliability from the perspective of buyers |
| Industry reorganization | Valuation multiples may increase due to benefits of scale |
| Expansion into growth markets | Future growth is likely to be evaluated |
In other words, PE fund products are more than just funds.
The ability to improve management itself becomes the fund's value.
Strengths of Japanese PE
The reason behind the attention that Japanese PE funds for small and medium-sized enterprises such as J-STAR are attracting is the unique structure of Japanese companies.
In Japan, there are many companies that have technology, customer bases, and regional market share, but are unable to grow due to management issues and succession issues.
| Common issues faced by Japanese companies | Reasons why PE is easy to enter |
|---|---|
| Lack of successors | Be able to take over business succession |
| Personalized management | A management system can be established |
| Delay in IT adoption | There is room for DX and operational efficiency |
| The industry is fragmented | You can create scale with roll-ups |
| Non-core business | Aim for independent growth with carve-out |
In such areas, the involvement of a PE fund can improve management systems, recruitment, finance, sales, M&A, etc., and increase corporate value.
Rollup Strategy
One technique that PE funds often use is roll-up.
Roll-up is a strategy to increase the size of a company by acquiring and merging small and medium-sized companies in the same industry.
| Effect | Content |
|---|---|
| Expand sales scale | Increase market share by integrating multiple companies |
| Cost reduction | Integrate purchasing, management departments, and systems |
| Utilization of human resources | Managerial and specialized human resources can be used within the group |
| Improving valuation multiples | Large companies may be more easily valued than small companies |
Many industries in Japan are fragmented.
Therefore, roll-ups can be an important growth vehicle for Japanese-style PE.
How do PE funds make money?
The revenue sources of PE fund management companies are generally divided into management fees and success fees.
| Source of revenue | Contents |
|---|---|
| Management fee | Continuous fee received for fund management |
| Success fee | Compensation received when investment results exceed a certain level |
| Related Fees | Fees related to projects and support may occur |
From an investor's perspective, the most important thing for PE funds is to increase corporate value and generate profits from sales.
From the perspective of a fund management company, the success of its investees is directly linked to its reputation, funding for the next fund, and remuneration.
That is why PE funds are deeply involved in post-investment support.
Why did MTU look attractive?
J-STAR announced its capital participation in MTU on March 3, 2025.
The published materials describe MTU as a health tech company that fuses medical care and IT, and introduces it as providing medical security cloud services for medical institutions and dental clinics.
It was also predicted that the demand for services would increase due to the increase in cyber-attacks on medical institutions and the shortage of security personnel.
From a PE fund's perspective, the following factors tend to be attractive.
| Elements | Attractiveness from a PE perspective |
|---|---|
| Medical DX | Social issues and market expansion are easily linked |
| Cybersecurity | High necessity and continued demand is likely to be expected |
| SaaS/Cloud | Easy to be evaluated as a recurring revenue model |
| For medical institutions | It tends to appear that there are specializations and barriers to entry |
| Room for strengthening business management | Seems to be compatible with PE hands-on support |
This combination may have seemed like a deal for a medium-sized PE like J-STAR to apply its existing management support know-how to a growth area.
Questions asked in the MTU incident
Then, on May 13, 2026, it was reported that the former MTU representative was arrested on suspicion of defrauding a fund company of approximately 1.63 billion yen.
TBS NEWS DIG reports that the former MTU representative is suspected of giving false explanations regarding the estimated sales for 2024 and the track record of implementation at medical institutions.
On the other hand, FNN Prime Online also reports that the former representative denies the charges.
Therefore, the matter is currently at the suspicion stage, and the final determination of the facts will be left to future investigation and judicial proceedings.
However, the issues in investment practice are clear.
| Points of discussion | Things that should have been confirmed |
|---|---|
| Sales | Contracts, billing, deposits, taxes, and alignment with customer payment records |
| Customer | Independent confirmation to medical institutions |
| Product | Production environment, usage log, API communication, operation history |
| SaaS Metrics | ARR, Churn Rate, Actual Billing, Active Usage |
| Media/PR | Are you confusing exposure with proof of existence? |
The MTU case shows the importance of verifying the existence of a business through independent channels, rather than just looking at submitted documents.
Difference between real companies and intangible assets companies
There are many businesses in which PE funds like J-STAR have traditionally excelled, such as factories, stores, logistics, service industries, and medical/nursing care-related businesses, where it is easy to check on-site operations.
Of course, these businesses also have fraud risks.
However, it is also true that there are relatively many ways to check the actual situation, such as the site, equipment, personnel, inventory, customer visits, and store sales.
On the other hand, the subject of confirmation changes for AI, SaaS, and medical DX.
| Real company | Intangible asset type company |
|---|---|
| Factories, equipment, stores, personnel | Codes, logs, data, usage status |
| You can see the inventory and the site | You need to see the difference between the demo and the actual production |
| Easy to compare sales and actual sales | Need to verify the quality of ARR and KPI |
| On-site investigation is effective | Technical DD is important |
For intangible asset-based companies, sales materials, customer lists, demo screens, and KPI materials may not be enough.
You need to check whether it is actually being used in production, whether there are actual charges, and whether it is consistent with the customer's usage log.
Turning point in the PE industry
What the MTU case showed is that the primary battleground for PE funds is changing.
Traditional PE has demonstrated its strengths in relatively tangible areas such as business succession, manufacturing, store-based services, industry restructuring, and carve-outs.
However, in the future, investment will increase in the following areas.
- A.I. -SaaS
- data business
- Medical DX
- Cybersecurity
- Cloud service
In these areas, financial DD or business DD alone is not enough.
The following checks are required:
| New DD | Contents |
|---|---|
| Technical DD | Confirmation of source code, development system, and technical debt |
| SaaS DD | Verification of ARR, cancellation rate, usage log, and retention rate |
| Data DD | Data quality, rights, acquisition methods, possibility of utilization |
| Cyber DD | Security system, vulnerabilities, operation history |
| Forensic DD | Verification of fraud, circular transactions, and fictitious sales |
In an era where PE funds acquire digital companies, competitiveness lies not only in the ability to improve management, but also in the ability to verify the reality of technology and data.
Implications for investors
What individual investors should learn from this incident is not to doubt professional investors.
Rather, it is so difficult to confirm the existence of intangible asset businesses that even professionals can overlook it.
When looking at investment news, check the following points:
| What to see | Why |
|---|---|
| What does a PE fund improve? | Value improvement cannot be determined by mere acquisition news |
| Are the target company's sales converted into cash? | Check for fictitious sales and collection delays |
| Are customers really using it? | Implementation history and actual usage are different |
| Is the technology in production? | Cannot be determined from a demo alone |
| Is the borrowing and acquisition price reasonable? | The loss will be large in the event of failure |
In growth themes like AI and medical DX, the stronger the story, the more important it is to confirm reality.
Summary
J-STAR is an investment company that handles PE investments for small and medium-sized enterprises in Japan.
Official information states that the company aims to maximize business value by building business strategies together with the managers of investee companies.
What was questioned in the MTU incident was not just J-STAR.
As PE funds expand their investment targets from the real economy to the digital economy, the industry-wide challenge is how to confirm the reality of sales, customers, technology, and data.
What future PE funds will need is not only the ability to improve management.
This is technology DD and forensic DD to help identify intangible asset type companies such as AI, SaaS, medical DX, and cybersecurity.
The MTU incident is not a story of failure by professional investors, but rather an event that calls into question the verification capabilities necessary for Japanese PE to move into the next era.
Source
- J-STAR Co., Ltd. official website: https://www.j-star.co.jp/
- J-STAR Co., Ltd. "J-STAR's investment criteria and themes.": https://www.j-star.co.jp/en/about-en/about-investment-en
- J-STAR Co., Ltd. “About capital participation in MTU Co., Ltd.” (March 3, 2025): https://www.j-star.co.jp/wp-content/uploads/2025/02/20250303_MTU%E6%A0%AA%E5%BC%8F%E4%BC%9A%E7%A4%BE%E3%81%B8%E3%81%AE%E8%B3%87%E6%9C%AC%E5%8F%82%E5%8A%A0%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6.pdf
- TBS NEWS DIG "The former president of a medical startup (38) was arrested on suspicion of fraud after defrauding a fund company of over 1.6 billion yen on the pretext of selling the company after lying about ``sales of about 800 million yen.'': https://newsdig.tbs.co.jp/articles/-/2657125?display=1
- FNN Prime Online "Former president of a medical startup arrested on suspicion of defrauding an investment fund of approximately 1.6 billion yen after offering to take over the company, saying it had annual sales of 800 million yen": https://www.fnn.jp/articles/-/1043917