SINOVAC BIOTECH LTD. NOTICE OF SPECIAL MEETING OF SHAREHOLDERS NOTICE IS HEREBY GIVEN that a Special Meeting of Shareholders of Sinovac Biotech Ltd. (the " Company ") will be held on Tuesday, 8 July 2025 at 8:00 p.m. Atl

SINOVAC BIOTECH LTD.

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS

HEREBY GIVEN that a Special Meeting of Shareholders of Sinovac Biotech Ltd. (the "Company") will be

held on Tuesday, 8 July 2025 at 8:00 p.m. Atlantic Standard Time (Wednesday, 9 July 2025 at 8:00

a.m. China Standard Time) pursuant to a requisition made by Cede & Co., as the registered holder of 10,780,820 common

shares of the Company, at the request of SAIF Partners IV L.P., the beneficial owner of such shares.

The meeting will be held at Stapleton Chambers

Inc., Suite No. 2, Stapleton House, Stapleton Lane, Saint John's, Antigua and Barbuda with online participation made

available via a secure videoconferencing platform.

BUSINESS TO BE CONDUCTED:

The meeting is convened for the purpose of considering

and, if thought fit, passing the following resolutions as ordinary resolutions:

To remove the following directors from

office (including from any committee of the Board of Directors of the Company) with immediate effect:

and any other person or persons elected

or appointed to the Board of Directors of the Company without shareholders' approval after 8 February 2025 and up to and including

the date of the Special Meeting (other than any person set forth in Resolution 2 below).

To elect the following persons as directors

of the Company, with immediate effect:

such other business as may properly come before the Special Meeting or any adjournment thereof, including, without limitation, the consideration

of any resolutions duly proposed as an alternative to the two resolutions set out above, or any matters incidental or ancillary to the

above resolutions or any alternative resolutions.

The Board of Directors has fixed 19 May 2025

as the record date for determining the shareholders entitled to receive notice of, and to attend and vote at, the Special Meeting. Subject

to the provisions of the International Business Corporations Act Cap. 222 (the Act'), only valid shareholders of record at

the close of business on that date (Atlantic Standard Time) will be entitled to vote.

PROXIES AND MEETING MATERIALS:

Details regarding proxy voting procedures, meeting

access, and other relevant documentation will be provided in due course and not later than twenty-one (21) days prior to the date fixed

for the Special Meeting.

Shareholders are entitled to attend the Special

Meeting in person or to be represented by proxy. A proxy form and accompanying materials will be circulated in advance of the Special

Meeting, and the deadline for the return of completed proxies shall be communicated at that time.

DIRECTOR STATEMENTS:

In accordance with section 71 of the Act,

any director whose removal is being proposed is entitled to submit a written statement. If received, any such statements will be

distributed to shareholders in accordance with section 71(3) of the Act.

At the Company's annual general meeting

held on 6 February 2018, the Company's old board of directors (consisting of Weidong Yin, Kenneth Lee, Simon Anderson, Yuk

Lam Lo and Mei Meng) (the "Old Board") was validly replaced with a new board of directors (consisting of Yuk Lam Lo,

Guowei Wang, Haifeng Qiu, Jianzeng Cao and Pengfei Li) (the "New Board").

Even though the Old Board had ceased to be the

board of directors of the Company on 6 February 2018, the Old Board remained in de facto control of the Company until the

Judicial Committee of the Privy Council issued its judgment in January 2025 in legal proceedings brought by 1Globe Capital, LLC,

a minority shareholder, finding and declaring, among other matters, that at the Company's annual general meeting on 6 February 2018,

the New Board had replaced the Old Board.

During the period 6 February 2018 to

January 2025, the Old Board purported to issue shares in the capital of the Company to certain persons (the "Disputed

Shares"). The Old Board had no authority to issue any shares in the capital of the Company following its removal on 6

Following the Privy Council's order, the

new board of directors of the Company has been taking, and continues to take, steps to identify the Disputed Shares. Following identification

of the Disputed Shares, the Company will take the necessary steps to achieve the cancellation of the Disputed Shares.

The Company's position is that the Disputed

Shares were not validly issued and that the purported holders of the Disputed Shares are not entitled to receive notice of, or vote at,

the Special Meeting.

Please note that this Notice does not amount

to a confirmation that you are a valid shareholder in the Company or entitled to vote at the Special Meeting.

BY ORDER OF THE BOARD

DATED this 19th day of May 2025