Samjo Management, LLC increased its stake in the software and engineering service company, PDF Solutions, (PDFS +0.19%) turning what was the second-largest holding into the fund's largest.
What happened
According to a filing with the Securities and Exchange Commission published on November 13, 2025, Samjo Management, LLC acquired 184,925 additional shares of PDF Solutions (PDFS +0.19%) in the third quarter. The fund's total holding increased to 551,250 shares, with a reported market value of $14,233,275 as of September 30, 2025.
What else to know
- This buy increased PDF Solutions to 11.1% of Samjo Management's 13F assets under management.
Top holdings after the filing:
- NASDAQ: PDFS: $43,170,240 (11.1% of AUM)
- NASDAQ: INSE: $30,065,902 (7.7% of AUM)
- NYSE: GENI: $29,562,202 (7.7% of AUM)
- NASDAQ: THRY: $23,356,904 (6.1% of AUM)
- NASDAQ: AIOT: $22,985,260 (6.0% of AUM)
- As of November 12, 2025, shares were priced at $25.97, down 20.9% over one year, underperforming the S&P 500 by 36.07 percentage points.
- PDF Solutions reported trailing twelve months revenue of $206,706,000 and a net loss of $53,000.
- The position was previously 8.4% of the fund's AUM as of the prior quarter.
Company Overview
| Metric | Value |
|---|---|
| Price (as of market close 2025-11-12) | $25.97 |
| Market Capitalization | $1.03 billion |
| Revenue (TTM) | $206.71 million |
| Net Income (TTM) | ($0.05 million) |
Company Snapshot
- Offers proprietary software platforms for manufacturing analytics, process control, and test operations, as well as physical intellectual property, electrical measurement hardware, and characterization services for the semiconductor industry.
- Generates revenue primarily through software licensing (including SaaS), hardware sales, and professional services focused on improving semiconductor yield, reliability, and manufacturing efficiency.
- Serves integrated device manufacturers, fabless semiconductor companies, foundries, equipment manufacturers, and electronics manufacturing suppliers globally.
PDF Solutions, Inc. is a technology company specializing in advanced software and hardware solutions for semiconductor manufacturing and analytics. The company's integrated offerings help clients optimize production processes, improve yield, and accelerate time-to-market for complex integrated circuits. With a global customer base and a focus on data-driven manufacturing intelligence, PDF Solutions leverages proprietary technologies to provide a competitive edge in the evolving semiconductor ecosystem.
Foolish take
PDF Solutions is not only the top stock among Samjo Management, LLC’s current holdings, but it is also the only one with a double-digit AUM among the 59 tickers held by the fund.
Moreover, the 20% increase in position size made it the largest position, as previously mentioned, up from the second-largest in Q2. It was also the largest increase by dollar amount, though the fund increased the position sizes in six other stocks by a greater percentage.
Nonetheless, Samjo targets individual stocks from a variety of industries, so the added interest in PDF Solutions is notable.
Furthermore, it appears to have bought the stock at a relative discount. While low profitability makes its P/E ratio meaningless, it sells at a 31 forward P/E and likely picked up the additional shares at an approximate 25 forward multiple.

NASDAQ: PDFS
Key Data Points
Finally, it appears to have bought shares at near five-year lows, meaning it was likely bargain hunting when it added shares of PDF Solutions.
Glossary
Stake: The ownership interest or investment a fund or individual holds in a company.
13F reportable assets under management (AUM): The total value of securities managed by a fund, as reported in quarterly SEC Form 13F filings.
Net position change: The difference in the value or size of a fund's holding in a security after a transaction.
Assets under management (AUM): The total market value of investments that a fund or manager oversees on behalf of clients.
Trailing twelve months (TTM): The 12-month period ending with the most recent quarterly report.
Integrated device manufacturers: Companies that both design and manufacture semiconductor chips in-house.
Fabless semiconductor companies: Firms that design semiconductor chips but outsource manufacturing to third-party foundries.
Foundries: Specialized semiconductor manufacturing plants that produce chips designed by other companies.
Proprietary software platforms: Software solutions owned and controlled by a company, not available for public use or modification.
SaaS (Software as a Service): A software delivery model where applications are accessed online by subscription rather than installed locally.
Yield (in semiconductors): The percentage of functional chips produced from a manufacturing batch.
Characterization services: Technical services that analyze and measure the properties and performance of semiconductor devices.

