International composite material stocks double within the year, Shanghai's mysterious private equity firm Xinxi Capital secures a paper profit of 5 billion

Glass fiber track ignites a surge in limit-up waves.

Recently, the stock price of International Composite Materials has been rising steadily. As of the close on the 26th, its share price reached 15.60 yuan per share, with a year-to-date increase of 122.86%.

In this round of rally, besides the controlling shareholder Yuntianhua Group, Shanghai Xinxin Capital Management Co., Ltd. (hereinafter “Xinxin Capital”) has become the biggest winner.

Data shows that before the listing of International Composite Materials, Xinxin Capital invested approximately 806 million yuan, acquiring 462 million shares. To date, Xinxin Capital still holds 331 million shares, with a market value of about 5.164 billion yuan. Including gains from reductions, the total unrealized profit from this investment has reached 5.022 billion yuan.

In fact, International Composite Materials is just one part of Xinxin Capital’s investment portfolio. In recent years, Xinxin Capital has also invested in projects such as Heyuan Bio, Raythink Micro-Nano, Maiwei Bio, Junshi Biosciences, and successfully backed the shell company Guohao Xin Ying, which went public through a backdoor listing of Tainpu Shares.

Up over 120% this year

Recently, the stock price of International Composite Materials repeatedly hit new highs, with its market value breaking through 50 billion yuan. Since 2026, the company’s cumulative increase has exceeded 120%.

Looking at the longer term, the company’s stock price has risen from 3.64 yuan per share at the end of June 2025 to the current 15.60 yuan per share, a range increase of 328.57%.

The immediate catalyst for this rally was the new wave of price hikes driven by “electronic fabric.” As a core raw material for PCB boards, electronic fabric plays a decisive role in the high-temperature resistance, impact resistance, and dielectric properties of PCBs.

It can be said that in any scenario involving PCB boards—whether in smartphones, wireless earbuds, or other consumer electronics, or AI servers, computing cabinets, new energy vehicle control systems, or even satellite internet ground equipment—electronic fabric is indispensable.

With the continuous acceleration of AI infrastructure construction, demand for electronic fabric is also rapidly increasing. For example, as AI servers evolve from traditional CPU architectures to GPU cluster architectures, the number of PCB layers generally exceeds 20, directly increasing the per-machine consumption of electronic fabric.

In the context of increasingly important supply chain security, leading companies are also actively deploying. It is reported that NVIDIA CEO Jensen Huang recently traveled to Japan to negotiate with key electronic fabric suppliers such as Nitto Denko; Apple is also actively communicating with the Japanese government to secure the supply of critical raw materials.

Driven by strong demand, electronic fabric prices are rising sharply. Data from Zhuochuang Information shows that in October and December 2025, and January and February 2026, ordinary electronic fabric experienced four consecutive rounds of price increases, with the cycle shortening from quarterly to monthly.

According to Honghe Technology’s disclosed Q3 2025 operating data, the average selling price of electronic fabric rose from 3.74 yuan per meter at the end of 2024 to 4.97 yuan per meter, a 33% increase. CITIC Securities also pointed out in a research report that the price of mainstream 7628 electronic fabric still has room to rise, potentially reaching 8 yuan per meter.

Benefiting from industry prosperity and its own technological advantages, International Composite Materials’ profitability has significantly improved. In the first three quarters of 2025, the company achieved operating revenue of 6.413 billion yuan, up 19.01% year-on-year; net profit attributable to shareholders was 273 million yuan, turning from a loss of 157 million yuan in the same period last year into a substantial profit.

Xinxin Capital’s unrealized gains reach 5 billion yuan

The continuous surge in International Composite Materials’ stock price has also revealed the key players behind the scenes.

Public information shows that International Composite Materials was founded in 1991, initially controlled by Chongqing Glass Fiber Factory. In 2013, Yuntianhua Group Co., Ltd. (hereinafter “Yuntianhua Group”), a state-owned enterprise in Yunnan, took control and became its largest shareholder.

Since then, through multiple capital increases and an IPO, Yuntianhua Group’s shareholding has decreased to 60.01%, but it remains the largest shareholder, holding 2.263 billion shares, with no reduction. Based on current stock prices, this stake’s market value has reached 353.03 billion yuan.

It is noteworthy that as an important energy and chemical platform in Yunnan Province, Yuntianhua Group has seen significant investment returns since 2026. Besides International Composite Materials, it also holds 699 million shares of Yuntianhua listed on A-shares, accounting for 38.36% of the total share capital. As of now, this stake’s market value is about 31.14 billion yuan, up from 18.74 billion yuan at the end of Q3 2025.

Unlike the state-controlled major shareholder, the second largest shareholder of International Composite Materials is a private equity firm from Shanghai—Xinxin Capital.

Public information shows that this private equity firm, established in 2015, was not very prominent in the capital market initially. However, just before International Composite Materials launched its first capital increase in 2017, Xinxin Capital quickly established Yunnan Yunxi Equity Investment Partnership (Limited Partnership) to participate precisely in the private placement.

According to the prospectus, at that time, Xinxin Capital, together with China Cinda and Jianxin Investment, participated in the capital increase plan of International Composite Materials. Xinxin Capital proposed to subscribe for 576 million shares, accounting for about 53% of the total increase, with an investment scale far exceeding that of China Cinda and Jianxin Investment combined. If successful, Xinxin Capital would hold 16.72% of the company’s shares.

However, because by the end of 2018, Xinxin Capital failed to pay the remaining 371 million shares’ subscription amount of 645 million yuan on time, International Composite Materials ultimately canceled this portion of shares. Xinxin Capital’s actual subscription was only 356 million yuan for 204 million shares.

Before the listing, Xinxin Capital made another move, acquiring 259 million shares from debt-to-equity holders for 450 million yuan. After this acquisition, it held a total of 463 million shares, accounting for 15.09% of the total pre-IPO share capital, officially becoming the second largest shareholder.

After the IPO, Xinxin Capital gradually opened the exit channel. From June to July 2025, it reduced 75.4176 million shares, cashing out about 278 million yuan. As the stock price continued to rise, from October to December of the same year, it reduced another 56.5632 million shares, cashing out 386 million yuan.

Currently, Xinxin Capital still holds 331 million shares of International Composite Materials, with a market value of about 5.164 billion yuan. Including previous cash-outs, its total unrealized gains on this project have reached 5.022 billion yuan, with an investment return rate of 623.08%.

Why would a private equity firm established only two years ago make such precise and large bets on International Composite Materials? A clue may lie in the partner structure of the Yunnan Yunxi Equity Investment Partnership it established.

Data shows that Interpat Platinum Co., Ltd. (hereinafter “Interpat”), which holds 17.28% of the fund, is not only an important supplier to International Composite Materials but also long-term provided transfer and loan services, maintaining close relations.

According to Interpat’s 2023 prospectus (draft), from 2020 to 2022, International Composite Materials purchased precious metals from Interpat for 188 million yuan, 528 million yuan, and 212 million yuan respectively. In 2022, it also sold 130 million yuan worth of rhodium to Interpat as a supplier.

Besides raw material transactions, Interpat also provided transfer and loan channels, helping International Composite Materials obtain financing from banks. From 2020 to 2022, Interpat used its bank accounts to help the company secure bank loans totaling 2.545 billion yuan, 1.377 billion yuan, and 217 million yuan respectively, with a total of 4.139 billion yuan over three years.

This intertwined business and capital flow may be the key reason why Xinxin Capital can make such precise bets.

Alchemy of Lan Youjin

Xinxin Capital’s ability to realize over 5 billion yuan in unrealized gains from the International Composite Materials project also heavily relies on its founder Lan Youjin’s rich capital experience.

From public resumes, Lan Youjin started his career at Huayi Investment Group Co., Ltd., serving as head of the investment development department. Later, he joined Shanghai Venture Capital Management Co., Ltd. as an investment manager. Two years later, he joined Shanghai Rongzheng Investment Co., Ltd., founded by Zheng Peimin, as a partner, gradually gaining management experience.

In 2006, Lan Youjin joined Xin Hengji International (Group) Co., Ltd., founded by Gao Jingde, as China Investment Director. According to Caixin’s 2014 report, Xin Hengji is a comprehensive multinational investment conglomerate based in Hong Kong, focused on the Chinese mainland market, with assets exceeding 60 billion HKD.

Subsequently, over nearly ten years within the Xin Hengji system, Lan Youjin served as general manager of its wholly owned subsidiary China Optoelectronics Investment Co., Ltd., and of its controlling subsidiary Jiangsu Wrun Optoelectronics Co., Ltd., transforming from a pure investor into an operator.

It was only in 2015 that he officially left the “Xin Hengji system” to establish his own venture capital platform—Xinxin Capital—and recruited Li Yijun, general manager of the financial division of Mianyang Wanshi Tonghui Assets, a “Wanxiang system” company, as a partner.

It is worth noting that Xinxin Capital’s start-up is closely related to Lan Youjin’s network built during his time at Xin Hengji. His first investment was in Ma Hong, a former colleague at Xin Hengji.

Reportedly, Ma Hong previously worked at Century Jingyuan, a semiconductor company invested in by Xin Hengji, and served alongside Lan Youjin at Jiangsu Century Chip Optoelectronics Co., Ltd., under the “Xin Hengji system.”

However, Century Jingyuan faced financial difficulties as early as 2009 and eventually became a “bad project.” Ma Hong resigned and founded Raythink Micro-Nano. Besides Ma Hong, director Jiang Bin, employee supervisor Wei Huijuan, and former chairman Fang Ping of Raythink Micro-Nano all came from Century Jingyuan.

After Lan Youjin established Xinxin Capital, Ma Hong not only served on its board but also joined the investment committee. Xinxin Capital was the first professional institutional investor to invest in Raythink Micro-Nano.

The prospectus shows that in 2015, Lan Youjin acquired 3 million shares of Raythink Micro-Nano from Ma Hong at par value for 3 million yuan; in 2016, his fund further acquired 9 million shares for 24 million yuan.

After multiple rounds of capital increases, Lan Youjin and his funds held a total of 12.8571 million shares of Raythink Micro-Nano. In 2019, the company successfully went public. On the day of lock-up expiration, the stock closed at 65.26 yuan per share, with the holdings valued at about 839 million yuan, unrealized gains exceeding 812 million yuan, and a return of over 30 times, earning Xinxin Capital its “first pot of gold.”

Besides International Composite Materials and Raythink Micro-Nano, Lan Youjin’s Xinxin Capital has also invested in Heyuan Bio, Maiwei Bio, Junshi Biosciences, Zhixiang Jintai, and the shell company Guohao Xin Ying, gradually building its own investment landscape.