[SCHEDULE 13D/A] Sinovac Biotech, Ltd SEC Filing

Rhea-AI Filing Summary

Advantech Capital L.P. and three affiliated Cayman entities filed Amendment No. 2 to their Schedule 13D on Sinovac Biotech Ltd. (ticker SVA) dated 14 July 2025.

• Ownership: The four reporting persons jointly hold 5,851,423 common shares, equal to 8.14 % of Sinovac’s 71,860,702 outstanding shares (per the 2023 Form 20-F). Voting and dispositive power are shared; none is held solely.
• Key Event Update (Item 4): • 7 July 2025 – Antigua High Court issued an injunction blocking several shareholders, including the reporting persons, from voting at a requisitioned Special Meeting.
  • 8 July 2025 – Eastern Caribbean Court of Appeal stayed that injunction, clearing the way for the meeting.
  • Same day – The Special Meeting proceeded despite an attempt to adjourn. Shareholders approved both proposals submitted by SAIF Partners IV L.P. and elected SAIF’s slate of directors.
  • Yumin Qiu, a partner at Advantech Capital, was elected and accepted a board seat.
• Continuing Dispute: On 10 July 2025 the ousted directors issued a press release disputing the vote; on 11 July 2025 the newly elected board announced its first meeting, signalling an ongoing governance contest.
• Future Intentions: The filers state they have no present plan that would trigger the additional transactions listed in Item 4(a)-(j) of Schedule 13D, but may reconsider depending on Sinovac’s performance and discussions with other shareholders. They expressly disclaim forming a “group” with other holders.
• Administrative Details: All signatures were executed by Yan Yang as authorised signatory/director for each entity.

The filing signals an activist milestone: a 8 % holder has helped change Sinovac’s board composition, yet litigation and duelling press releases highlight unresolved control issues that could affect corporate strategy and share-holder value.

Positive

• Advantech and affiliates secured a board seat for partner Yumin Qiu, signalling increased influence over Sinovac’s strategic direction.
• The group holds 5.85 million shares, representing a significant 8.14 % economic interest that aligns board participation with ownership.
• Court of Appeal stay enabled shareholder voting, demonstrating the group’s ability to navigate legal challenges successfully.

Negative

• Litigation and conflicting press releases from ousted directors create uncertainty around the validity of the Special Meeting results.
• An earlier injunction highlights ongoing legal exposure and potential costs until governance issues are fully resolved.

Insights

Securities Analyst

TL;DR: 8.14 % stake, successful board seat, legal dispute persists—potential governance catalyst for SVA.

The amendment confirms Advantech’s meaningful 8 % position and its active participation in reshaping Sinovac’s board through SAIF’s proposals. Activist involvement can drive strategic or capital-allocation changes, often unlocking value. However, the contested legitimacy of the vote and prior injunction introduce headline and litigation risk, which may create short-term volatility. No immediate plan to raise or cut the stake is disclosed, limiting visibility on further accumulation or exit. Overall, the development is potentially value-enhancing but remains contingent on the new board gaining uncontested control.

Corporate Governance Expert

TL;DR: Court stay allowed contested meeting; board now split between old and new factions—material governance overhang.

The stay of the Antigua injunction illustrates how cross-border legal venues can complicate shareholder rights. While the meeting approved SAIF’s slate, the ousted directors’ subsequent press release signals refusal to concede, raising the spectre of continued litigation in Caribbean courts and possible delay in implementing new governance. Advantech’s disclosure complies with Item 4, yet its disclaimer of group status could become a focus if regulators or courts probe coordinated action. Until the board’s legitimacy is resolved, Sinovac faces execution risk in decision-making and potential regulatory scrutiny, impacting investor confidence.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 2)

SINOVAC BIOTECH LTD.

(Name of Issuer)

Common Shares

(Title of Class of Securities)

P8696W104

(CUSIP Number)

Xingluo Zhu
Suite 1707-08, 17/F, One Exchange Square, 8 Connaught Place, Central
Hong Kong, K3, 000000
86-10-8593-5676

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

07/08/2025

(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. P8696W104

1

Name of reporting person

Advantech Capital L.P.

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)

WC

5

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

6

Citizenship or place of organization

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 5,851,423.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 5,851,423.00

11

Aggregate amount beneficially owned by each reporting person

5,851,423.00

12

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

13

Percent of class represented by amount in Row (11)

8.14 %

14

Type of Reporting Person (See Instructions)

PN

Comment for Type of Reporting Person:

Comments to item 13: Based on 71,860,702 Common Shares of the Issuer outstanding as of March 31, 2024 according to the Issuer's annual report on Form 20-F for the fiscal year ended December 31, 2023 (the "2023 Annual Report").

SCHEDULE 13D

CUSIP No. P8696W104

1

Name of reporting person

Advantech Capital Partners Ltd.

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)

WC

5

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

6

Citizenship or place of organization

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 5,851,423.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 5,851,423.00

11

Aggregate amount beneficially owned by each reporting person

5,851,423.00

12

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

13

Percent of class represented by amount in Row (11)

8.14 %

14

Type of Reporting Person (See Instructions)

CO

Comment for Type of Reporting Person:

Comments to item 13: Based on 71,860,702 Common Shares of the Issuer outstanding as of March 31, 2024 according to the 2023 Annual Report.

SCHEDULE 13D

CUSIP No. P8696W104

1

Name of reporting person

Green Vision Partners 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)

WC

5

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

6

Citizenship or place of organization

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 5,851,423.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 5,851,423.00

11

Aggregate amount beneficially owned by each reporting person

5,851,423.00

12

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

13

Percent of class represented by amount in Row (11)

8.14 %

14

Type of Reporting Person (See Instructions)

CO

Comment for Type of Reporting Person:

Comments to item 13: Based on 71,860,702 Common Shares of the Issuer outstanding as of March 31, 2024 according to the 2023 Annual Report.

SCHEDULE 13D

CUSIP No. P8696W104

1

Name of reporting person

Prime Success, L.P.

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)

WC

5

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

6

Citizenship or place of organization

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 5,851,423.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 5,851,423.00

11

Aggregate amount beneficially owned by each reporting person

5,851,423.00

12

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

13

Percent of class represented by amount in Row (11)

8.14 %

14

Type of Reporting Person (See Instructions)

PN

Comment for Type of Reporting Person:

Comments to item 13: Based on 71,860,702 Common Shares of the Issuer outstanding as of March 31, 2024 according to the 2023 Annual Report.

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Common Shares
(b)	Name of Issuer: SINOVAC BIOTECH LTD.
(c)	Address of Issuer's Principal Executive Offices: No. 39 Shangdi Xi Road, Haidian District, Beijing, CHINA , 100085.
Item 1 Comment: This Amendment No.2 to Schedule 13D is being filed on behalf of Advantech Capital L.P., Advantech Capital Partners Ltd., Green Vision Partners Limited and Prime Success, L.P. (each, a "Reporting Person") to amend the Schedule 13D relating to the common shares, par value $0.001 per share (the "Common Shares"), of Sinovac Biotech Ltd. (the "Issuer"), filed by the Reporting Persons on March 25, 2025, as amended by Amendment No. 1 filed by the Reporting Persons on April 10, 2025 (collectively, the "Original Schedule 13D"). The items herein amend the information disclosed under the corresponding items of the Original Schedule 13D. Capitalized terms used herein and not otherwise defined have the meanings given to them in the Original Schedule 13D.
Item 4.	Purpose of Transaction
	Item 4 is hereby supplemented and amended by adding the following: On July 7, 2025, the High Court of Antigua and Barbuda granted an interim injunction prohibiting the Reporting Persons and certain other shareholders from voting their shares at the Special Meeting (the "Injunction Order"). On July 8, 2025, the Court of Appeal of the Eastern Caribbean Supreme Court issued an order staying the Injunction Order (the "Stay Order"). After the Court of Appeal issued the Stay Order, the Special Meeting of Shareholders of the Issuer requisitioned by SAIF Partners IV L.P. ("SAIF") (the "Special Meeting") was convened. Mr. Chiang Li delivered a short statement and then purported to adjourn the Special Meeting. The Reporting Persons understand that the shareholders attending the Special Meeting then continued with the Special Meeting chaired by an incumbent director of the Issuer. The Reporting Persons voted their shares by proxy in favor of SAIF's proposals at the Special Meeting. The Reporting Persons understand that the shareholders of the Issuer approved both of SAIF's proposals at the Special Meeting and elected the nominees proposed by SAIF, including Mr. Yumin Qiu, a partner of Advantech Capital, to be the directors of the Issuer. Mr. Yumin Qiu accepted the appointment and intends to serve as a member of the board of directors of the Issuer. The Reporting Persons understand that on July 10, 2025, the previous directors removed at the Special Meeting issued a press release disputing the election results of the Special Meeting, and on July 11, 2025, the new board of directors of the Issuer elected at the Special Meeting issued a press release announcing the convening of the first board meeting. Except as set forth herein as may be necessary for defending their lawful interests in the Issuer in relation to the 2018 Private Placement, either alone or in coordination with any one or more shareholders of the Issuer, the Reporting Persons have no present plan or intention that would result in or relate to any of the transactions described in clauses (a) through (j) of Item 4 of Schedule 13D. Depending on discussions with other shareholders of the Issuer, the financial condition, results of operations and prospects of the Issuer and other factors that the Reporting Persons deem relevant, the Reporting Persons may take steps and pursue other plans or proposals that relate to or would result in any of the matters set forth in clauses (a) through (j) of Item 4 of Schedule 13D. The filing of this Amendment No. 2 shall not be construed as an admission that the Reporting Persons and their affiliates, on the one hand, and any other shareholders of the Issuer and their affiliates, on the other hand, are a group, or have agreed to act as a group with each other for purposes of Section 13(d) of the Act or for any other purpose. The Reporting Persons expressly disclaim beneficial ownership of the common shares beneficially owned by other shareholders of the Issuer.
Item 5.	Interest in Securities of the Issuer
(e)	Not applicable.
Item 6.	Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer
	Item 6 is hereby supplemented and amended by adding the following: Item 4 of this Amendment No. 2 to Schedule 13D is incorporated herein by reference.

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.

Advantech Capital L.P.

Signature:	/s/ Yan Yang
Name/Title:	Yan Yang / Authorized Signatory
Date:	07/14/2025

Advantech Capital Partners Ltd.

Signature:	/s/ Yan Yang
Name/Title:	Yan Yang / Authorized Signatory
Date:	07/14/2025

Green Vision Partners Limited

Signature:	/s/ Yan Yang
Name/Title:	Yan Yang / Director
Date:	07/14/2025

Prime Success, L.P.

Signature:	/s/ Yan Yang
Name/Title:	Yan Yang / Authorized Signatory
Date:	07/14/2025

FAQ

How many Sinovac (SVA) shares does Advantech Capital own?

The filing shows 5,851,423 common shares, representing 8.14 % of Sinovac’s outstanding stock.

What court actions affected Sinovac’s Special Meeting in July 2025?

On 7 July 2025 the Antigua High Court issued an injunction barring voting; on 8 July 2025 the Eastern Caribbean Court of Appeal stayed that order.

Were SAIF Partners’ proposals approved at the Special Meeting?

Yes. Shareholders— including Advantech via proxy— approved both SAIF proposals and elected its director nominees.

Who from Advantech Capital joined Sinovac’s board?

Advantech partner Mr. Yumin Qiu was elected and accepted a position as director.

Does Advantech plan further transactions with Sinovac?

The group states it has no present plans triggering Item 4(a)-(j) actions but may reconsider based on future conditions.

Where is Sinovac Biotech’s principal executive office located?

The address is No. 39 Shangdi Xi Road, Haidian District, Beijing, China 100085.