[SCHEDULE 13D/A] Zhihu Inc. SEC Filing

Rhea-AI Filing Summary

Zhihu Inc. received an updated ownership report showing that Plus Channel Limited and Kastle Limited together beneficially own 22,909,037 Class A ordinary shares, representing 9.0% of the company’s Class A shares as of October 31, 2025. This stake consists of 22,041,537 Class A shares in the form of 7,347,179 ADSs and 867,500 Class A shares held directly by Plus Channel Limited.

The reporting parties state that these shares are held on trust under Zhihu’s 2022 share incentive plan. Since the prior amendment, they continued repurchasing Zhihu shares on the New York Stock Exchange and the Hong Kong Stock Exchange, using Zhihu’s working capital, including a repurchase of 30,000 Class A shares in the form of 10,000 ADSs on November 18, 2025 that increased their ownership to 9.0%, which is described as a material change.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 4)

Zhihu Inc.

(Name of Issuer)

Class A ordinary shares, par value US$0.000125 per share

(Title of Class of Securities)

98955N207

(CUSIP Number)

Tsang Suk Han
23/F, Li Po Chun Chambers, 189 Des Voeux Road Central
Hong Kong, K3, 00000
85227602518

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

11/18/2025

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP No. 98955N207

1

Name of reporting person

Plus Channel Limited

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

SC

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

VIRGIN ISLANDS, BRITISH

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 22,909,037.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 22,909,037.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

22,909,037.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

9.0 %

14

Type of Reporting Person (See Instructions)

CO

Comment for Type of Reporting Person:

Shareholding includes (i) 22,041,537 Class A ordinary shares in the form of 7,347,179 ADSs and (ii) 867,500 Class A ordinary shares held by Plus Channel Limited. The percentage of the class of securities is calculated by dividing the number of shares beneficially owned by the reporting person by a total of 254,416,106 issued and outstanding Class A ordinary shares of the issuer as of October 31, 2025.

SCHEDULE 13D

CUSIP No. 98955N207

1

Name of reporting person

Kastle Limited

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

SC

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

HONG KONG

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 22,909,037.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 22,909,037.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

22,909,037.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

9.0 %

14

Type of Reporting Person (See Instructions)

HC

Comment for Type of Reporting Person:

Shareholding includes (i) 22,041,537 Class A ordinary shares in the form of 7,347,179 ADSs and (ii) 867,500 Class A ordinary shares held by Plus Channel Limited. The percentage of the class of securities is calculated by dividing the number of shares beneficially owned by the reporting person by a total of 254,416,106 issued and outstanding Class A ordinary shares of the issuer as of October 31, 2025.

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Class A ordinary shares, par value US$0.000125 per share
(b)	Name of Issuer: Zhihu Inc.
(c)	Address of Issuer's Principal Executive Offices: 18 Xueqing Road, Haidian District, Beijing, CHINA , 100083.
Item 1 Comment: This Amendment No. 4 to Schedule 13D (this "Amendment No. 4") amends and supplements the Statement on Schedule 13D originally filed with the U.S. Securities and Exchange Commission on March 20, 2025 (the "Original Schedule 13D"), as amended by Amendment No.1 to Schedule 13D filed on April 7, 2025, Amendment No. 2 to Schedule 13D filed on June 3, 2025 and Amendment No.3 to Schedule 13D filed on September 19, 2025 (together, the "Statement") filed by Plus Channel Limited and Kastle Limited (each a "Reporting Person" and collectively the "Reporting Persons") with respect to Class A ordinary shares of Zhihu Inc. (the "Issuer"). Except as provided herein, this Amendment No. 4 does not modify any of the information previously reported on the Statement. Capitalized terms used but not defined in this Amendment No. 4 have the meanings ascribed to them in the Statement.
Item 2.	Identity and Background
(d)	No
(e)	No
Item 3.	Source and Amount of Funds or Other Consideration
	Item 3 of the Original Schedule 13D is hereby amended and supplemented by the following: Since the filing of the Amendment No. 3, the Reporting Persons continued to conduct share repurchases on the New York Stock Exchange and the Stock Exchange of Hong Kong Limited. The funds were provided by the Issuer from its working capital.
Item 4.	Purpose of Transaction
	Item 4 of the Original Schedule 13D is hereby amended and supplemented by the following: The information set forth in Item 3 is hereby incorporated by reference in its entirety. The Reporting Persons hold the Class A ordinary shares they beneficially owned on trust under the Issuer's share incentive plan adopted in 2022.
Item 5.	Interest in Securities of the Issuer
(a)	Item 5 of the Original Schedule 13D is hereby amended and supplemented by the following: The responses of each Reporting Person to Rows (7) through (13) of the cover pages of this Amendment No. 2 are hereby incorporated by reference in this Item 5. The Reporting Persons in aggregate own 22,909,037 Class A ordinary shares of the Issuer, including (i) 22,041,537 Class A ordinary shares in the form of 7,347,179 ADSs and (ii) 867,500 Class A ordinary shares held by Plus Channel Limited. Plus Channel Limited is wholly-owned by Kastle Limited. The percentage of the class of securities is calculated by dividing the number of shares beneficially owned by the reporting person by a total of 254,416,106 issued and outstanding Class A ordinary shares of the issuer as of October 31, 2025.
(b)	22,909,037; see the response to Item 5(a).
(c)	Plus Channel Limited had been repurchasing the issuer's shares during the past 60 days, with a repurchase of 30,000 Class A ordinary shares in the form of 10,000 ADSs on November 18, 2025 that made the shareholding of the Reporting Persons to increase to 9.0%, constituting a material change.
(d)	Except as disclosed in this Schedule 13D, no other person has the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the Class A ordinary shares beneficially owned by the Reporting Persons.
(e)	Not applicable.
Item 6.	Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer
	The information set forth in Items 3, 4 and 5 is hereby incorporated by reference in its entirety. To the best knowledge of the Reporting Persons, except as provided herein, there are no other contracts, arrangements, understandings or relationships (legal or otherwise) between the Reporting Persons and between any of the Reporting Persons and any other person with respect to any securities of the Issuer, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, divisions of profits or loss, or the giving or withholding of proxies, or a pledge or contingency, the occurrence of which would give another person voting power over the securities of the issuer.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Plus Channel Limited

Signature:	/s/ TSANG SUK HAN
Name/Title:	TSANG SUK HAN, Director of Kastle Limited which is the director of Plus Channel Limited
Date:	11/21/2025

Kastle Limited

Signature:	/s/ TSANG SUK HAN
Name/Title:	TSANG SUK HAN, Director
Date:	11/21/2025

FAQ

What ownership stake in Zhihu Inc. (ZH) do Plus Channel Limited and Kastle Limited report?

Plus Channel Limited and Kastle Limited report beneficial ownership of 22,909,037 Class A ordinary shares of Zhihu Inc., representing 9.0% of the Class A shares as of October 31, 2025.

How are the 22,909,037 Zhihu (ZH) shares held by Plus Channel and Kastle structured?

The 22,909,037 shares include 22,041,537 Class A shares in the form of 7,347,179 ADSs and 867,500 Class A shares held by Plus Channel Limited.

What recent share repurchase activity affected Plus Channel and Kastle’s stake in Zhihu (ZH)?

Plus Channel Limited repurchased 30,000 Class A ordinary shares in the form of 10,000 ADSs on November 18, 2025, which increased the reporting persons’ ownership to 9.0% and is described as a material change.

Who provided the funds for the Zhihu (ZH) share repurchases mentioned in this ownership update?

The share repurchases conducted on the New York Stock Exchange and the Hong Kong Stock Exchange were funded with Zhihu Inc.’s working capital.

In what capacity do Plus Channel Limited and Kastle Limited hold Zhihu (ZH) shares?

Plus Channel Limited and Kastle Limited state that they hold the Class A ordinary shares they beneficially own on trust under Zhihu Inc.’s share incentive plan adopted in 2022.

What is the relationship between Plus Channel Limited and Kastle Limited in the context of Zhihu (ZH) shares?

Plus Channel Limited is wholly owned by Kastle Limited, and each is a reporting person for the 22,909,037 Class A ordinary shares of Zhihu Inc. they beneficially own.