DISCLOSEABLE TRANSACTIONS: (1) BINDING TERM SHEET IN RELATION TO THE PROPOSED FINANCING OF PROBIO CAYMAN AND THE DEEMED DISPOSAL OF EQUITY INTEREST IN PROBIO CAYMAN IN RELATION TO THE SERIES A FINANCING; (2) THE PURCHASE OF SHARES AND DEEMED DISPOSAL OF EQUITY INTEREST IN LEGEND BIOTECH IN RELATION TO THE PURCHASE; AND (3) RESUMPTION OF TRADING

This announcement appears for information purposes only and does not constitute an invitation or offer to acquire, purchase or subscribe for the securities.

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this announcement, make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this announcement.

Genscript Biotech Corporation

金斯瑞生物科技股份有限公司 *

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 1548)

DISCLOSEABLE TRANSACTIONS

1. BINDING TERM SHEET IN RELATION TO THE PROPOSED FINANCING OF PROBIO CAYMAN AND THE DEEMED DISPOSAL

OF EQUITY INTEREST IN PROBIO CAYMAN IN RELATION

1. TO THE SERIES A FINANCING

2. THE PURCHASE OF SHARES AND DEEMED DISPOSAL OF EQUITY INTEREST IN LEGEND BIOTECH IN RELATION
   TO THE PURCHASE

AND

(3) RESUMPTION OF TRADING

PROPOSED FINANCING OF PROBIO CAYMAN

The Board is pleased to announce that on 14 May 2021 (before trading hours, Hong Kong time), the Company and the Investor entered into the binding Term Sheet in relation a proposed Series A Financing of Probio Cayman, an indirect wholly-owned subsidiary of the Company, pursuant to which, prior to the Probio Closing, the Company will through its subsidiary, Probio BVI, subscribe for convertible bonds in the amount of US$70 million, which shall be convertible into the Probio Shares.

The Investor will subscribe for Series A Preferred of Probio Cayman of an aggregate investment amount of the Series A Financing, being US$150 million.

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The Company will issue a Probio Warrant to the Investor exercisable (i) within 24 months of the Probio Closing or (ii) prior to the last practical date required by applicable law or regulation, or any requirement of any stock exchange or regulatory authority in an initial public offering (or if no such date is required, immediately prior to the completion of the initial public offering), whichever is earlier, to purchase the Probio Warrant Shares at a price per share equal to 1.32 times the Original Purchase Price for up to an aggregate amount of US$125 million.

THE PURCHASE

The Board is pleased to announce that on 13 May 2021 (New York time) (before trading hours on 14 May 2021, Hong Kong time), Legend Biotech entered into the Subscription Agreement, whereby Legend Biotech agreed to: (i) issue and sell, and the Purchaser agreed to purchase an aggregate of 20,809,850 Legend Shares at an aggregate consideration of US$300.0 million, and

1. issue to the Purchaser the Legend Warrant to subscribe for and purchase from Legend Biotech up to an aggregate of 10,000,000 Legend Shares at an aggregate exercise price of US$200.0 million.

LISTING RULES IMPLICATION

As at the date of this announcement, Probio Cayman is indirectly wholly-owned by the Company through its wholly-owned subsidiary Probio BVI. Upon the Probio Closing, the equity interest of Probio BVI in Probio Cayman will be diluted to 82.95%, assuming the Convertible Bonds are not converted into Probio Shares. Therefore, the Series A Financing as contemplated under the Term Sheet constitutes a deemed disposal of the Company's equity interest in Probio Cayman under Rule 14.29 of the Listing Rules.

As at the date of this announcement, Legend Biotech is non-wholly owned subsidiary of the Company. Upon the Legend Closing, the equity interest of the Company in Legend Biotech will be diluted to 58.31%. Therefore, the Purchase as contemplated under the Subscription Agreement constitutes a deemed disposal of the Company's equity interest in Legend Biotech under Rule 14.29 of the Listing Rules.

According to Rule 14.22 of the Listing Rules, the Stock Exchange will aggregate a series of transactions and treat them as if they were one transaction if they are all completed within a 12-month period or are otherwise related. As each of the Aggregated Transactions involves a reduction of the percentage shareholding of the Company in Legend Biotech and constitutes a deemed disposal on the part of the Company, the Aggregated Transactions will be required to be aggregated pursuant to Rule 14.22 of the Listing Rules.

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As the highest applicable percentage ratio (as defined under the Listing Rules) in respect of the deemed disposal arising from the Aggregated Transactions, in aggregate, exceeds 5% but is less than 25%, the Aggregated Transactions constitute a discloseable transaction for the Company and are subject to the reporting and announcement requirements under Chapter 14 of the Listing Rules.

RESUMPTION OF TRADING

At the request of the Company, trading of shares of the Company was halted with effect from 9:00 a.m. on Friday, 14 May 2021. Application has been made by the Company to the Stock Exchange for the resumption of trading of the shares of the Company with effect from 13:30 p.m. on Friday, 14 May 2021.

The Series A Financing and the Purchase may or may not proceed and that the Shareholders and potential investors of the Company are advised to exercise caution when dealing in the Shares.

PROPOSED FINANCING OF PROBIO CAYMAN

This announcement is made by Genscript Biotech Corporation (the "Company") pursuant to Rule

13.09 of the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited (the "Listing Rules") and the Inside Information Provisions under Part XIVA of the Securities and Futures Ordinance (Chapter 571 of the Laws of Hong Kong).

The Board is pleased to announce that on 14 May 2021 (before trading hours, Hong Kong time), the Company and the Investor entered into the binding Term Sheet in relation the possible Series A Financing of Probio Cayman, an indirect wholly-owned subsidiary of the Company. The terms and conditions of the Series A Financing are subject to further negotiations between the Company and the Investor.

Major Terms of the Term Sheet

1. Date
   14 May 2021 (before trading hours, Hong Kong time)
2. Parties:
   The Company and the Investor (collectively, the "Parties")
   To the best of the Directors' knowledge, information and belief, and having made all reasonable enquiries, the Investor, and their respective ultimate beneficial owners/investment managers/ general partners is an Independent Third Party.

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1. Convertible Bonds
   Prior to the Probio Closing, the Company will through its subsidiary, Probio BVI, subscribe for convertible bonds in the amount of US$70 million, which shall be convertible into the Probio Shares (the "Convertible Bonds").
   At any time (i) within 24 months of the Probio Closing or (ii) prior to the last practical date required by applicable law or regulation, or any requirement of any stock exchange or regulatory authority in an initial public offering (or if no such date is required, immediately prior to the completion of the initial public offering), whichever is earlier, the Convertible Bonds shall be convertible at the option of the holder thereof into such number of Probio Shares as are equal to the quotient of (i) US$70 million, divided by (ii) a price per Probio Share equal to 1.32 times of the Original Purchase Price.
2. Series A Financing
   Probio Cayman agreed to issue, and the Investor agreed to subscribe for Series A Preferred of Probio Cayman, being the rank of shares of Probio Cayman having the most senior rights, preferences and privileges, of an aggregate investment amount of the Series A Financing, being US$150 million.
3. Valuation
   The price per share of the Series A Preferred of Probio Cayman (the "Original Purchase Price") shall be the price determined on the basis of a pre-money valuation of Probio Cayman of US$730 million (which shall not include any employee incentive scheme to be adopted immediately after the Probio Closing).
4. Probio Warrant
   The Company will issue to the Investors a Probio Warrant, exercisable at any time (i) within 24 months of the Probio Closing or (ii) prior to the last practical date required by applicable law or regulation, or any requirement of any stock exchange or regulatory authority in an initial public offering (or if no such date is required, immediately prior to the completion of the initial public offering), whichever is earlier, to purchase the Probio Warrant Shares at a price per share equal to 1.32 times the Original Purchase Price for up to an aggregate amount of US$125 million.
5. Series A Preferred Rights
   The holders of the Series A Preferred shall be entitled to certain rights, including dividends in preference to other class of shares of Probio Cayman, liquidation preference, right to convert to Probio share, redemption right, as converted voting rights, and other customary anti-dilution, preemptive right, right of first refusal, registration rights and information rights. The detailed terms of such rights are to be set out in the definitive transaction agreements between the Parties.

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1. Termination of Rights
   The rights of the Investors under this term sheet, other than the registration rights, shall automatically terminate upon the earlier of (i) immediately prior to the consummation of an initial public offering, and (ii) the consummation of a deemed liquidation event such a merger, disposition of all or substantially all of the assets or licensing of material intellectual properties of Probio Cayman.
2. Binding Effect
   The Term Sheet shall be binding on the Parties and is intended to be replaced by definitive transaction agreements to be executed and delivered by the Parties.

THE PURCHASE

The Board is pleased to announce that on 13 May 2021 (New York time) (before trading hours on 14 May 2021, Hong Kong time), Legend Biotech entered into the Subscription Agreement, whereby Legend Biotech agreed to: (i) issue and sell, and the Purchaser agreed to purchase an aggregate of 20,809,850 Legend Shares (the "Purchased Shares") at an aggregate consideration of US$300.0 million, and (ii) issue to the Purchaser a warrant (the "Legend Warrant") to subscribe for and purchase from Legend Biotech up to an aggregate of 10,000,000 Legend Shares (the "Legend Warrant Shares") at an aggregate exercise price of US$200.0 million.

Purchase Agreement

Date: 13 May 2021 (New York time) (before trading hours on 14 May 2021, Hong Kong time)

Parties:

1. Legend Biotech, as the issuer; and
2. LGN Holdings Limited, as the "Purchaser".

To the best of the Directors' knowledge, information and belief, and having made all reasonable enquiries, the Purchaser, and its ultimate beneficial owners/investment managers/general partners is an Independent Third Party.

The principal terms of the Subscription Agreement is summarized as follows:

Consideration

According to the Subscription Agreement, the aggregate purchase price for the Purchased Shares is approximately US$300.0 million and the aggregate exercise price for the Legend Warrant Shares is US$200.0 million.

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