Zhihu has invested 1.5 billion RMB in Cao Xi
Zhihu, a long-established community in the Chinese Internet ecosystem, has quietly embraced AI in a new way.
On September 6, Zhihu announced on the Hong Kong Stock Exchange that it plans to invest 1.5 billion yuan to become a major limited partner of the AI fund under Cao Xi, former partner of HSG and founding partner of Monolith. This subscribed investment accounts for about one-third of Zhihu's cash assets on its books.
Against the backdrop where major Internet giants are generally scaling back their operations and strictly controlling capital expenditures, the significance of this move speaks for itself.
Although this investment is still subject to the approval of the general meeting of shareholders, the signal is clear enough: Zhihu intends to use capital to secure a ticket to the core circle of the AI industry.
Interestingly, public information shows that Zhihu had no public direct cooperation with Cao Xi before, but Zhihu CEO Zhou Yuan's long-term focus on AI technology and Cao Xi's precise bets on the AI track have laid the groundwork for this cooperation.
From "Developing AI" to "Investing in AI"
According to the announcement on the Hong Kong Stock Exchange, Beijing Wise Exploration Technology, a wholly-owned subsidiary of Zhihu, will act as a limited partner (LP) to subscribe for the shares of "Tianjin Monolith Xingsheng Equity Investment Partnership". The fund will mainly invest in early-stage projects such as AI infrastructure, foundation models, robotics and AI applications, and this matter is still subject to the approval of the general meeting of shareholders.
Behind this fund is Cao Xi, former partner of HSG and founder of Monolith. In other words, Zhihu has become an LP and is betting on the most core and cutting-edge tracks in the AI industry.
Source: Announcement screenshot
Looking back at Zhihu's history of AI exploration, it seems to have "started early but arrived late".
In 2023, Zhihu launched the "Zhihai AI" large model, trying to embed AI capabilities into its Q&A community, but its influence was limited compared with ByteDance's Doubao and Baidu's Ernie. The AI search product "Zhihu Direct Answer" launched in 2024 is more in line with the community's characteristics and is regarded as one of the core starting points, but the large-scale monetization of new AI businesses is still in the early verification stage.
In fact, Zhihu is not without a foundation in the AI field. As early as April 2023, Zhihu participated in the angel round investment of Bionic Intelligence. Li Dahai, the CEO of Bionic Intelligence, was once the CTO of Zhihu. During his tenure at Zhihu, Li Dahai was responsible for the overall management of Zhihu's big data team, content circulation and the expansion of new AI businesses.
This connection shows that Zhihu's bet on AI is not a random decision, but a traceable continuation of its previous layout.
Zhihu explained the main reasons for this subscription in the announcement: On the one hand, through the subscription, Zhihu is expected to broaden its channels to participate in high-quality investment opportunities in artificial intelligence and technology enterprises, and further deepen its understanding of the evolution of artificial intelligence technologies, products and the development of business models.
On the other hand, from the perspective of business synergy, it will help Zhihu further understand the development of large model technologies, product forms and application scenarios, and may provide potential technical application or business cooperation opportunities for fields such as Zhihu Direct Answer, expert data solutions, and AI-related content and IP development.
This also reveals Zhihu's deeper intention: it not only wants to obtain financial returns, but also hopes to make up for its shortcomings in AI R&D capabilities through capital expansion. After all, the high investment and uncertainty of self-developed large models have discouraged many Internet companies. Entering a front-line AI fund as an LP can maintain sensitivity to the trend of cutting-edge technologies at a relatively low risk.
Pressure and Determination in Financial Reports
The other side of betting on AI is the realistic pressure reflected in Zhihu's financial reports.
In the first half of 2026, Zhihu achieved a total revenue of 1.342 billion yuan, a year-on-year decrease of 7.2%; the net loss was 45.918 million yuan, turning from profit to loss year-on-year.
Breaking down the revenue structure, the pressure is more specific.
The core marketing service revenue was 390.4 million yuan, a year-on-year decrease of about 7%. This sector, which once supported Zhihu's commercialization, is facing the dual squeeze of shrinking advertiser budgets and intensifying traffic competition.
Other revenues (including vocational training, expert data solutions, etc.) reached 123 million yuan, accounting for 9.2% of the total revenue, also declining year-on-year.
The only segment that maintained positive growth was paid content and IP operation revenue, which recorded 828 million yuan in the first half of the year, a year-on-year increase of 4.4%. This growth was mainly driven by the increase in IP operation revenue.
Zhihu CEO Zhou Yuan once said that the company's community foundation maintains resilience, and AI is becoming a new medium connecting users and content, promoting its long-accumulated content, IP and expert capabilities to enter a wider range of applications and business scenarios.
At this year's Q1 performance meeting, Zhihu's management revealed that AI has been applied to the whole chain of IP development of short dramas and comic dramas, including storyboarding, image generation, script creation and content distribution, to improve the efficiency of content adaptation. The year-on-year growth of IP operation revenue in the second quarter shows that this path has begun to contribute incremental revenue. However, the company has not separately disclosed the specific revenue generated by AI-generated content, and its actual driving effect on the overall business is still difficult to quantify and evaluate.
This set of financial data outlines Zhihu's situation: the overall revenue is shrinking, the only growing business relies on AI, and AI itself requires continuous investment. As of the end of the second quarter of 2026, Zhihu's cash and equivalents, time deposits and short-term investments totaled 4.424 billion yuan, with abundant cash reserves. The management defines new businesses including AI as being in the "commercialization verification stage", and subsequent resource investment will depend on market demand, customer value and return on investment. This also reflects the management's prudent consideration of input-output ratio.
When competitors are using large models to reconstruct content production one after another, Zhihu must find its own entry ticket for AI, and AI investment in the primary market just provides a strategic window. Exchanging 1.5 billion yuan of LP contribution for in-depth observation rights of the cutting-edge AI ecosystem and potential cooperation opportunities is more rational than continuing to increase investment in self-developed large models from the perspective of cost-benefit.
In a sense, this investment allows Zhihu to enter the AI industry chain as an LP, trying to reposition itself in the AI era.
What is the Background of the AI Hunter Zhihu is Betting On
The person who can make Zhihu spend this sum of money is Cao Xi.
As a former partner of HSG, Cao Xi founded Monolith Capital in 2021, with an AUM exceeding 10 billion yuan. He has made numerous successful bets on the AI track —— Moonlight (Kimi), DeepSeek, MetaX, Unitree Robotics, almost forming half of the map of AI unicorns.
The market's recognition of him is not limited to Zhihu. Since 2026, many listed companies such as iHealth, Century Huatong, and Visual China have successively announced their investments in Cao Xi's funds.
In July this year, iHealth announced that it plans to use no more than 100 million yuan of its own funds to participate in the subscription of Monolith Xingque's shares. Monolith Xingque is a fund under Monolith Capital. In the same month, Century Huatong announced that its subsidiary Shanghai Shengqu Shumeng plans to invest 150 million yuan to become the LP of Tianjin Monolith Xingque, which is managed by Cao Xi's Monolith Capital.
These industrial capitals are willing to entrust real money to Cao Xi, not only because of his high hit rate on the AI track, but also because of his ability to build bridges between technology and business. The industry insight and post-investment empowerment demonstrated by Cao Xi are exactly the scarce value that industrial LPs value most.
For Zhihu, choosing Cao Xi is no accident. Although the two sides have no public direct equity cooperation in the past, Zhihu's founder Zhou Yuan's long-term focus on AI technology coincides with Cao Xi's precise bets on the AI track in terms of philosophy.
More importantly, among the invested enterprises of Monolith Capital, there are many targets with potential synergy with Zhihu: large model companies need high-quality data, and Zhihu just has the highest-quality Q&A corpus of knowledge in the Chinese Internet; embodied intelligence and robotics companies need scenario implementation, and the Zhihu community itself is an efficient channel for AI products to reach core users.
Whether this 1.5 billion yuan bet can bring new life to Zhihu in the AI era remains to be tested by time. At least at this moment, Zhihu is already at the poker table.
This article is from the WeChat official account "Lieyun Select", author: Han Wenjing, published with authorization from 36Kr.