UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16 UNDER

THE SECURITIES EXCHANGE ACT OF 1934

For the month of November 2021

Commission File Number: 001-39173

I-MAB

Suite 802, West Tower, OmniVision, 88 Shangke Road, Pudong District

Shanghai, 201210

People’s Republic of China

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F  ☒                     Form 40-F   ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ☐

EXPLANATORY NOTE

Exhibits 99.1, 99.2 and 99.3 to this current report on Form 6-K are incorporated by reference into the registration statement on Form F-3 of I-Mab (File No. 333-252793) and shall be a part thereof from the date on which this current report is furnished, to the extent not superseded by documents or reports subsequently filed or furnished.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: November 12, 2021

Exhibit Index

Exhibit 99.1 — Unaudited Condensed Consolidated Interim Financial Statements

Exhibit 99.2 — Discussion of Unaudited Financial Statements

Exhibit 99.3 — Updated Risk Factors

Exhibit 99.1

I-Mab

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Unaudited Interim Condensed Consolidated Financial Statements for the Six Months Ended June 30, 2020 and 2021

I-MAB

Consolidated Balance Sheets as of December 31, 2020 and

Unaudited Interim Condensed Consolidated Balance Sheet as of June 30, 2021

(All amounts in thousands, except for share and per share data, unless otherwise noted)

The accompanying notes are an integral part of these unaudited interim condensed consolidated financial statements.

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I-MAB

Unaudited Interim Condensed Consolidated Statements of Comprehensive Loss

For the Six Months Ended June 30, 2020 and 2021

The accompanying notes are an integral part of these unaudited interim condensed consolidated financial statements.

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I-MAB

Unaudited Interim Condensed Consolidated Statements of Changes in Shareholders’ Equity (Deficit)

For the Six Months Ended June 30, 2020 and 2021

(All amounts in thousands, except for share and per share data, unless otherwise noted)

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Unaudited Interim Condensed Consolidated Statements of Changes in Shareholders’ Equity (Deficit) (Continued)

For the Six Months Ended June 30, 2020 and 2021

(All amounts in thousands, except for share and per share data, unless otherwise noted)

The accompanying notes are an integral part of these unaudited interim condensed consolidated financial statements.

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I-MAB

Unaudited Interim Condensed Consolidated Statements of Cash Flows

For the Six Months Ended June 30, 2020 and 2021

(All amounts in thousands, except for share and per share data, unless otherwise noted)

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Unaudited Interim Condensed Consolidated Statements of Cash Flows (Continued)

For the Six Months Ended June 30, 2020 and 2021

(All amounts in thousands, except for share and per share data, unless otherwise noted)

The accompanying notes are an integral part of these unaudited interim condensed consolidated financial statements.

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I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

1. PRINCIPAL ACTIVITIES AND ORGANIZATION

I-Mab (the “Company”) was incorporated in the Cayman Islands on June 30, 2016 as an exempted company with limited liability under the Companies Act of the Cayman Islands. The Company and its subsidiaries (together the “Group”) are principally engaged in discovering and developing transformational biologics in the fields of immuno-oncology and immuno-inflammation diseases in the People’s Republic of China (the “PRC”) and other countries and regions.

On January 17, 2020, the Company consummated its IPO on the Nasdaq Global Market, where 7,407,400 American Depositary Shares (“ADSs”) were issued at the price of US$14.00 per ADS for total gross proceeds of US$103.7 million. On February 10, 2020, the underwriters of the IPO have exercised their over-allotment option to purchase an additional 768,350 ADSs of the Company at the IPO price of US$14.00 per ADS. After giving effect to the exercise of the over-allotment option, the Company has issued and sold a total of 8,175,750 ADSs in the IPO, for total gross proceeds of US$114.5 million. Each ten ADSs represents twenty-three ordinary shares of the Company.

As of June 30, 2021, the Company’s principal subsidiaries are as follows:

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I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES

2.1 Basis of presentation

The accompanying unaudited interim condensed consolidated financial statements of the Group have been prepared in accordance with the accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information. Accordingly, they do not include all of the information and footnotes normally included in the annual financial statements prepared in accordance with U.S. GAAP. Certain information and footnote disclosures normally included in the annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted consistent with Article 10 of Regulation S-X. In the opinion of management, the Group’s unaudited interim condensed consolidated financial statements and accompanying notes include all adjustments (consisting of normal recurring adjustments) considered necessary for the fair statement of the Group’s financial position as of June 30, 2021, and results of operations and cash flows for the six months ended June 30, 2020 and 2021. Interim results of operations are not necessarily indicative of the results for the full year or for any future period. These unaudited interim condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements as of and for the year ended December 31, 2020, and related notes included in the Group’s audited consolidated financial statements. The financial information as of June 30, 2021 presented in the unaudited interim condensed consolidated financial statements is derived from the audited consolidated financial statements as of December 31, 2020.

Significant accounting policies followed by the Group in the preparation of the accompanying consolidated financial statements are summarized below.

2.2 Basis of consolidation

The accompanying consolidated financial statements reflect the accounts of the Company and all of its subsidiaries in which a controlling interest is maintained. All inter-company balances and transactions have been eliminated in consolidation.

The Group consolidates entities in which it has a controlling financial interest based on either the variable interest entity (VIE) or voting interest model. The Group is required to first apply the VIE model to determine whether it holds a variable interest in an entity, and if so, whether the entity is a VIE. If the Group determines it does not hold a variable interest in a VIE, it then applies the voting interest model. Under the voting interest model, the Group consolidates an entity when it holds a majority voting interest in an entity.

The Company accounts for investments in which it has significant influence but not a controlling financial interest using the equity method of accounting (see Note 8).

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Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.2 Basis of consolidation (continued)

VIE Model

An entity is considered to be a VIE if any of the following conditions exist: (a) the total equity investment at risk is not sufficient to permit the entity to finance its activities without additional subordinated financial support, (b) the holders of the equity investment at risk, as a group, lack either the direct or indirect ability through voting rights or similar rights to make decisions that have a significant effect on the success of the entity or the obligation to absorb the entity’s expected losses or right to receive the entity’s expected residual returns, or (c) the voting rights of some equity investors are disproportionate to their obligation to absorb losses of the entity, their rights to receive returns from an entity, or both and substantially all of the entity’s activities either involve or are conducted on behalf of an investor with disproportionately few voting rights.

Under the VIE model, limited partnerships are considered VIE unless the limited partners hold substantive kick-out or participating rights over the general partner. The Group consolidates entities that are VIEs when the Group determines it is the primary beneficiary. Generally, the primary beneficiary of a VIE is a reporting entity that has (a) the power to direct the activities that most significantly affect the VIE’s economic performance, and (b) the obligation to absorb losses of, or the right to receive benefits from, the VIE that could potentially be significant to the VIE.

As of December 30, 2020 and June 30, 2021, the Group determined that the one entity subject to the consolidation guidance is a VIE for which the Group is not the primary beneficiary.

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Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.3 Use of estimates

The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosures of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Estimates are used when accounting for amounts recorded in connection with acquisitions, including initial fair value determinations of assets and liabilities and other intangible assets as well as subsequent fair value measurements. Additionally, estimates are used in determining items such as fair value measurements of wealth management products, warrants and put right liabilities, impairment of accounts receivables, contract assets, other receivables, long-lived assets, intangible assets and goodwill, useful lives of property, equipment and software, recognition of right-of-use assets and lease liabilities, variable consideration in collaboration revenue arrangements, determination of the standalone selling price of each performance obligation in the Company’s revenue arrangements, valuation of share-based compensation arrangements and deferred tax assets valuation allowances. Management bases the estimates on historical experience, known trends and various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results could differ from those estimates.

2.4 Fair value measurements

Financial assets and liabilities of the Group primarily comprise of cash and cash equivalents, restricted cash, short-term investments, accounts receivable, contract assets, other receivables, short-term borrowings, accruals and other payables and put right liabilities. As of December 31, 2020 and June 30, 2021, except for short-term investments and put right liabilities, the carrying values of these financial assets and liabilities approximated their fair values because of their generally short maturities. The Group reports short-term investments and put right liabilities at fair value at each balance sheet date and changes in fair value are reflected in the consolidated statements of comprehensive loss.

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I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.4 Fair value measurements (continued)

The Group measures its financial assets and liabilities using inputs from the following three levels of the fair value hierarchy. The three levels are as follows:

Level 1 inputs are unadjusted quoted prices in active markets for identical assets that the management has the ability to access at the measurement date.

Level 2 inputs include quoted prices for similar assets in active markets, quoted prices for identical or similar assets in markets that are not active, inputs other than quoted prices that are observable for the asset (i.e., interest rates, yield curves, etc.), and inputs that are derived principally from or corroborated by observable market data by correlation or other means (market corroborated inputs).

Level 3 includes unobservable inputs that reflect the management’s assumptions about the assumptions that market participants would use in pricing the asset. The management develops these inputs based on the best information available, including the own data.

Assets and liabilities measured at fair value on a recurring basis

The Group measures its short-term investments and put right liabilities at fair value on a recurring basis. As the Group’s short-term investments and put right liabilities are not traded in an active market with readily observable prices, the Group uses significant unobservable inputs to measure the fair value of short-term investments and put right liabilities. These instruments are categorized in the Level 3 valuation hierarchy based on the significance of unobservable factors in the overall fair value measurement.

The following table summarizes the Group’s financial assets and liabilities measured and recorded at fair value on a recurring basis as of December 31, 2020 and June 30, 2021:

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I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.4 Fair value measurements (continued)

The roll forward of major Level 3 financial assets and financial liabilities are as follows:

See Note 8(b) for additional information about Level 3 put right liabilities measured at fair value on a recurring basis for as of December 31, 2020 and June 30, 2021.

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Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.5 Foreign currency translation

The Group uses Chinese Renminbi (“RMB”) as its reporting currency. The United States Dollar (“US$”) is the functional currency of the Group’s entities incorporated in the Cayman Islands, the United States of America (“U.S.”) and Hong Kong, the Australia Dollar (“AUD”) is the functional currency of the Group’s entity incorporated in Australia and the RMB is the functional currency of the Company’s PRC subsidiaries.

Transactions denominated in other than the functional currencies are translated into the functional currency of the entity at the exchange rates prevailing on the transaction dates. Assets and liabilities denominated in other than the functional currencies are translated at the balance sheet date exchange rate. The resulting exchange differences are recorded in the consolidated statements of comprehensive loss.

The consolidated financial statements of the Group are translated from the functional currency to the reporting currency, RMB. Assets and liabilities of the subsidiaries are translated into RMB using the exchange rate in effect at each balance sheet date. Income and expenses are translated at the average exchange rates prevailing for the year. Foreign currency translation adjustments arising from these are reflected in the accumulated other comprehensive loss. The exchange rates used for translation on December 31, 2020 and June 30, 2021 were US$1.00 = RMB6.5249 and RMB6.4601 respectively, representing the index rates stipulated by the People’s Bank of China.

Translations of balances in the consolidated balance sheets, consolidated statements of comprehensive loss, consolidated statements of changes in shareholders’ equity and consolidated statements of cash flows from RMB into US$ as of and for the six months ended June 30, 2021 are solely for the convenience of the readers and were calculated at the rate of US$1.00=RMB6.4566, representing the noon buying rate in The City of New York for cable transfers of RMB as certified for customs purposes by the Federal Reserve Bank of New York on June 30, 2021. No representation is made that the RMB amounts could have been, or could be, converted, realized or settled into US$ at that rate on June 30, 2021, or at any other rate. The US$ convenience translation is not required under U.S. GAAP and all US$ convenience translation amounts in the accompanying consolidated financial statements are unaudited.

2.6 Cash and cash equivalents

Cash and cash equivalents consist of cash on hand and bank deposits, which are unrestricted as to withdrawal and use. The Group considers all highly liquid investments with an original maturity date of three months or less at the date of purchase to be cash equivalents.

2.7 Restricted cash

Restricted cash consists of proceeds received from agent banks for employee’s exercise of stock options which will be paid to the employees. The Group has presented restricted cash separately from cash and cash equivalents in the consolidated balance sheets.

Cash, cash equivalents and restricted cash as reported in the consolidated statement of cash flows are presented separately on the consolidated balance sheet as follows:

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I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.8 Accounts receivable

Accounts receivable are stated at amortized cost less allowance for credit losses. The allowance for credit losses reflects the best estimate of future losses over the contractual life of outstanding accounts receivable and is determined on the basis of historical experience, specific allowances for known troubled accounts, other currently available information including customer financial condition, and both current and forecasted economic conditions.

2.9 Short-term investments

Short-term investments represent the investments issued by commercial banks or other financial institutions with a variable interest rate indexed to the performance of underlying assets within one year. These investments are stated at fair value. Changes in the fair value are reflected in the consolidated statements of comprehensive loss.

2.10 Property, equipment and software

Property, equipment and software are stated at cost less accumulated depreciation and amortization. Depreciation and amortization is computed using the straight-line method over the following estimated useful lives, taking into account of any estimated residual value:

The Group recognizes the gain or loss on the disposal of property, equipment and software in the consolidated statements of comprehensive loss.

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Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.11 Intangible assets

Intangible assets acquired in a business combination that are used in research and development activities, or in-process research and development (IPR&D) intangible assets, are considered indefinite lived until the completion or abandonment of the associated research and development efforts. During the period that those assets are considered indefinite lived, they are not amortized but are tested for impairment annually and more frequently if events or changes in circumstances indicate that it is more likely than not that the asset is impaired. If after assessing the totality of events and circumstances and their potential effect on significant inputs to the fair value determination the Group determines that it is not more likely than not that the indefinite-lived intangible is impaired, then the entity shall calculate the fair value of the intangible asset and perform the quantitative impairment test by comparing the fair value of the asset with its carrying amount. If the carrying amount exceeds its fair value, an impairment loss is recognized in an amount equal to that excess. For IPR&D assets, the impairment loss is recognized in research and development expenses in the consolidated statements of comprehensive loss.

Intangible assets with finite useful lives are amortized over their useful lives. The useful life of an intangible asset is the period over which the asset is expected to contribute directly or indirectly to the future cash flows of the Group. The Group uses the straight-line amortization method when the economic benefits of the intangible assets are consumed or otherwise used up cannot be reliably determined. In particular, the Group amortizes the IPR&D intangible assets with finite useful lives over 10 to 20 years on a straight-line basis. Intangible assets subject to amortization are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an intangible asset may not be recoverable. If circumstances require an intangible asset be tested for possible impairment, the Group first compares undiscounted cash flows expected to be generated by that asset to its carrying amount. If the carrying amount is not recoverable on an undiscounted cash flow basis, an impairment is recognized to the extent that the carrying amount exceeds its fair value. For IPR&D assets, the impairment loss is recognized in research and development expenses in the consolidated statements of comprehensive loss.

2.12 Impairment of long-lived assets

Long-lived assets, such as property, plant, and software, and intangible assets subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If circumstances require a long-lived asset or asset group be tested for possible impairment, the Company first compares undiscounted cash flows expected to be generated by that asset or asset group to its carrying amount. If the carrying amount of the long-lived asset or asset group is not recoverable on an undiscounted cash flow basis, an impairment is recognized to the extent that the carrying amount exceeds its fair value. Fair value is determined through various valuation techniques including discounted cash flow models, quoted market values and third-party independent appraisals, as considered necessary. As of December 31, 2020 and June 30, 2021, there was no impairment of the value of the Group’s long-lived assets.

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Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.13 Goodwill

Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. The Group allocates the cost of an acquired entity to the assets acquired and liabilities assumed based on their estimated fair values at the date of acquisition. The excess of the purchase price for acquisitions over the fair value of the net assets acquired, including other intangible assets, is recorded as goodwill. Goodwill is not amortized, but impairment of goodwill is tested on at least an annual basis or whenever events or changes in circumstances indicate that the carrying value of the asset may not be recoverable.

The Group first assesses qualitative factors to determine whether it is more likely than not that the fair value of the Group’s reporting unit is less than its carrying amount, including goodwill. The qualitative assessment includes the Group’s evaluation of relevant events and circumstances affecting the Group’s single reporting unit, including macroeconomic, industry, market conditions and the Group’s overall financial performance. If qualitative factors indicate that it is more likely than not that the Group’s reporting unit’s fair value is less than its carrying amount, then the Group will perform the quantitative impairment test by comparing the reporting unit’s carrying amount, including goodwill, to its fair value. If the carrying amount of the reporting unit exceeds its fair value, an impairment loss will be recognized in an amount equal to that excess. As of December 31, 2020 and June 30, 2021, the Group determined that there were no indicators of impairment of the goodwill.

2.14 Long-term investments

The Group’s long-term investments include equity investments in an affiliate in which it does not have a controlling financial interest, but has the ability to exercise significant influence over the operating and financial policies of the investee. The investment is accounted for using the equity method of accounting in accordance with ASC topic 323, Investments—Equity Method and Joint Ventures (“ASC 323”). Under the equity method, the Group initially records its investments at fair value. The Group subsequently adjusts the carrying amount of the investment to recognize the Group’s proportionate share of the equity investee’s net income or loss after the date of investment. When the liquidation rights and priorities as defined by an equity investment agreement differ from what is reflected by the underlying percentage ownership interests, applying the percentage ownership interest to U.S. GAAP net income in order to determine earnings or losses does not accurately represent the income allocation and cash flow distributions that will ultimately be received by the investors. As such, for this type of investments, the Group uses the Hypothetical Liquidation at Book Value (“HLBV”) method for allocating earnings or losses of the equity method investee. The HLBV method is considered as a balance sheet approach. Specifically, a calculation is prepared at each balance sheet date to determine the amount that the Group would receive if an equity investment entity were to liquidate all of its assets (as valued in accordance with U.S. GAAP) and distribute that cash to the investors based on the contractually defined liquidation priorities. The difference between the calculated liquidation distribution amounts at the beginning and the end of the reporting period, after adjusting for capital contributions and distributions, is the Group’s share of the earnings or losses from the equity investment for the period.

As it relates to the share-based compensation awarded by an equity method investee to its own employees, the Group recognizes its proportionate share of the compensation expense over the vesting period, included in the equity in loss of affiliate in the consolidated statements of comprehensive loss. As it relates to the share-based compensation awarded by the Group to the equity method investee employees that are based on the Group’s stock, when the other investors do not provide proportionate value to the investee or the Group does not receive any consideration, the Group expenses the entire cost associated with the award in the same period the costs are recognized by the investee, to the extent that the Group’s claim on the investee’s book value has not been increased. The expenses recognized by the Group is included in the equity in loss of affiliate in the consolidated statements of comprehensive loss.

The Group evaluates the equity method investment for impairment under ASC 323. An impairment loss on the equity method investments is recognized in losses when the decline in value is determined to be other-than-temporary. No impairment charge was recognized for the year ended December 31, 2020 and six months ended June 30, 2021.

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Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.15 Deferred subsidy income

Deferred subsidy income consists of deferred income from government grants. Government grants mainly consist of cash subsidies received by the Group’s subsidiaries in the PRC from local governments as support on expenses relating to certain projects. Grants received with government specified performance obligations are recognized as other income when all the obligations have been satisfied. If such obligations are not satisfied, the Group may be required to refund the subsidy. The Group recorded cash grants of RMB7,509 and RMB4,560 in deferred subsidy income as of December 31, 2020 and June 30, 2021 respectively.

2.16 Revenue recognition

The Group adopted Accounting Standard Codification (“ASC”) 606, Revenue from Contracts with Customers (Topic 606) (“ASC 606”) for all periods presented. Consistent with the criteria of Topic 606, the Group recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to receive in exchange for those goods or services.

Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. An the entity performs the following five steps to account for the arrangements that an entity determines are within the scope of ASC 606: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation.

Once a contract is determined to be within the scope of ASC 606 at contract inception, the Group audits the contract to determine which performance obligations it must deliver and which of these performance obligations are distinct. The Group recognizes as revenue the amount of the transaction price that is allocated to each performance obligation when that performance obligation is satisfied or as it is satisfied.

Collaboration revenue

At contract inception, we analyze its collaboration arrangements to assess whether they are within the scope of ASC 808, Collaborative Arrangements (“ASC 808”) to determine whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, we first determine if the collaboration is deemed to be within the scope of ASC 808. For any units of account that are reflective of a vendor-customer relationship those units of account are accounted for within the scope of ASC 606. For any units of account that are not accounted for under ASC 606 and therefore accounted for pursuant to ASC 808, an appropriate recognition method is determined and applied consistently.

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Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.16 Revenue recognition (continued)

Collaboration revenue (continued)

The Group’s collaborative arrangements may contain more than one unit of account, or performance obligation, such as grant of licenses of intellectual property rights, promises to provide research and development services and other deliverables. The collaborative arrangements do not include a right of return for any deliverable. When multiple units of account or performance obligations are identified within the arrangements, the Group must develop assumptions that require judgment to determine the stand-alone selling price for each performance obligation identified in the contract. In developing the stand-alone selling price for a performance obligation, the Group considers competitor pricing for a similar or identical product, market awareness of and perception of the product, expected product life and current market trends. In general, the consideration allocated to each performance obligation is recognized when the respective obligation is satisfied either by delivering a good or providing a service, limited to the consideration that is not constrained.

Licenses of Intellectual Property: Upfront non-refundable payments for licensing the Group’s intellectual property are evaluated to determine if the license is distinct from the other performance obligations identified in the arrangement. For the license that is determined to be distinct, the Group recognizes revenues in the amount of non-refundable, up-front fees allocated to the license at a point in time, upon which the license is transferred to the licensee and the licensee is able to use and benefit from the license.

Research and Development Services: The portion of the transaction price allocated to research and development services performance obligations is deferred and recognized as revenue over time as delivery or performance of such services provided to the Group’s customers occurs.

Milestone Payments: At the inception of each arrangement that includes development, commercialization, and regulatory milestone payments, the Group evaluates whether the milestones are considered probable of being reached and to the extent that a significant reversal of cumulative revenue would not occur in future periods, estimates the amount to be included in the transaction price using the most likely amount method. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Group recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Group re-evaluates the probability of achieving such development milestones and any related constraint, and if necessary, adjust the estimate of the overall transaction price. Any resulting adjustment is recorded on a cumulative catch-up basis, which would affect the Group’s reported revenues and earnings in the period of the adjustment.

Royalties: For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the sales-based royalties or milestone payments relate, the Group recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied).

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Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.16 Revenue recognition (continued)

Contract assets and liabilities

Contract assets primarily represent revenue earnings over time that are not yet billable based on the terms of the contracts. The Group does not have impairment losses associated with contracts with customers for the years ended December 31, 2020 and six months ended June 30, 2021.

Contract liabilities consist of fees invoiced or paid by the Group’s customers for which the associated performance obligations have not been satisfied and revenue has not been recognized based on the Group’s revenue recognition criteria described above.

Contract assets and contract liabilities are reported in a net position on an individual contract basis at the end of each reporting period. Contract assets are classified as current in the consolidated balance sheet when the Group expects to complete the related performance obligations and invoice the customers within one year of the balance sheet date, and as long-term when the Group expects to complete the related performance obligations and invoice the customers more than one year out from the balance sheet date. Contract liabilities are classified as current in the consolidated balance sheet when the revenue recognition associated with the related customer payments and invoicing is expected to occur within one year of the balance sheet date and as long-term when the revenue recognition associated with the related customer payments and invoicing is expected to occur in more than one year from the balance sheet date.

2.17 Value-added-tax (“VAT”) recoverable and surcharges

Value added tax recoverable represent amounts paid by the Group for purchases. The surcharges (i.e., Urban construction and maintenance tax, educational surtax, local educational surtax), vary from 6% to 12% of the value-added-tax depending on the tax-payer’s location. The deductible input VAT balance is included in the prepayments and other receivables in the consolidated balance sheets, and VAT payable balance is recorded in the accruals and other payables in the consolidated balance sheets.

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Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.18 Research and development expenses

Elements of research and development expenses primarily include (1) payroll and other related expenses of personnel engaged in research and development activities, (2) in-licensed patent rights fee of exclusive development rights of drugs granted to the Group, (3) expenses related to preclinical testing of the Group’s technologies under development and clinical trials such as payments to contract research organizations (“CRO”), investigators and clinical trial sites that conduct the clinical studies, (4) expenses to develop the product candidates, including raw materials and supplies, product testing, depreciation, and facility related expenses, and (5) other research and development expenses. Research and development expenses are charged to expenses as incurred when these expenditures are used for the Group’s research and development activities and have no alternative future uses.

The Group has acquired rights to develop and commercialize product candidates. Upfront payments that relate to the acquisition of a new drug compound, as well as pre-commercial milestone payments, are immediately expensed as acquired in-process research and development in the period in which they are incurred, provided that the new drug compound does not also include processes or activities that would constitute a “business” as defined under U.S. GAAP, the drug has not achieved regulatory approval for marketing and, absent obtaining such approval, has no established alternative future use. Milestone payments made to third parties subsequent to regulatory approval are capitalized as intangible assets and amortized over the estimated remaining useful life of the related product. All development expenditures are recognized in profit or loss when incurred, as long as the conditions enabling capitalization of development expenses as an asset have not yet been met.

2.19 Leases

In accordance with ASC 842 adopted on January 1, 2019, the Group determines if an arrangement is a lease at inception. Operating leases are included in operating lease right-of-use (“ROU”) assets, operating lease liability, and operating lease liability, non-current in the Group’s consolidated balance sheets. The Group does not have any finance leases since the adoption date.

ROU assets represent the Group’s right to use an underlying asset for the lease term and lease liabilities represent the Group’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. When determining the lease term, the Group includes options to extend or terminate the lease when it is reasonably certain that it will exercise that option, if any. As the Group’s leases do not provide an implicit rate, the Group uses its incremental borrowing rate, which it calculates based on the credit quality of the Group and by comparing interest rates available in the market for similar borrowings, and adjusting this amount based on the impact of collateral over the term of each lease.

The Group has elected to adopt the following lease policies in conjunction with the adoption of ASU 2016-02: (i) elect for each lease not to separate non-lease components from lease components and instead to account for each separate lease component and the non-lease components associated with that lease component as a single lease component; (ii) for leases that have lease terms of 12 months or less and does not include a purchase option that is reasonably certain to exercise, the Group elected not to apply ASC 842 recognition requirements; and (iii) the Group elected to apply the package of practical expedients for existing arrangements entered into prior to January 1, 2019 to not reassess (a) whether an arrangement is or contains a lease, (b) the lease classification applied to existing leases, and (c) initial direct costs.

In connection with the adoption of ASC 842, on January 1, 2019, the Group recorded an impact of RMB13,100 on its assets and RMB11,333 on its liabilities for the recognition of operating lease right-of-use-assets and operating lease liabilities, respectively, which are primarily related to the lease of the Group’s offices and warehouses. The adoption of ASC 842 did not have a material impact on the Group’s results of operations or cash flows.

20

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.20 Comprehensive loss

Comprehensive loss is defined as the changes in equity of the Group during a period from transactions and other events and circumstances excluding transactions resulting from investments by owners and distributions to owners. Among other disclosures, ASC 220, Comprehensive Income, requires that all items that are required to be recognized under current accounting standards as components of comprehensive loss be reported in a financial statement that is displayed with the same prominence as other financial statements. For each of the periods presented, the Group’s comprehensive loss includes net loss and foreign currency translation adjustments, which are presented in the consolidated statements of comprehensive loss.

2.21 Share-based compensation

The Group grants restricted shares and stock options to eligible employees and accounts for share-based compensation in accordance with ASC 718, Compensation—Stock Compensation.

Employees’ share-based compensation awards, if equity-classified, are measured at the grant date fair value of the awards and are recognized as expenses over the requisite period of the award, which is generally the vesting term of share-based payment awards.

A change in any of the terms or conditions of share-based awards is accounted for as a modification of the awards. The Group calculates incremental compensation expense of a modification as the excess of the fair value of the modified awards over the fair value of the original awards immediately before its terms are modified at the modification date. For vested awards, the Group recognizes incremental compensation cost in the period when the modification occurs. For awards not being fully vested, the Group recognizes the sum of the incremental compensation expense and the remaining unrecognized compensation expense for the original awards over the remaining requisite service period after modification.

Share-based compensation in relation to the restricted shares is measured based on the fair market value of the Group’s ordinary shares at the grant date of the award. Prior to the listing, estimation of the fair value of the Group’s ordinary shares involves significant assumptions that might not be observable in the market, and a number of complex and subjective variables, including discount rate, and subjective judgments regarding the Group’s projected financial and operating results, its unique business risks, the liquidity of its ordinary shares and its operating history and prospects at the time the grants are made. Share-based compensation in relation to the share options is estimated using the Binominal Option Pricing Model. The determination of the fair value of share options is affected by the share price of the Group’s ordinary shares as well as the assumptions regarding a number of complex and subjective variables, including the expected share price volatility, risk-free interest rate, exercise multiple and expected dividend yield. In addition, the forfeiture rate is estimated based on an analysis of the Group’s actual forfeitures and the appropriateness of the forfeiture rate will continue to be evaluated based on the actual forfeiture experience, analysis of employee turnover and other factors. The fair value of these awards was determined with the assistance from an independent third-party valuation firm.

21

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.22 Income taxes

The Group accounts for income taxes under the asset and liability method. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the enacted tax rates that expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is recorded if it is more likely than not that some portion or all of the deferred income tax assets will not be utilized in the foreseeable future.

The Group evaluates its uncertain tax positions using the provisions of ASC 740-10, Income Taxes, which prescribes a recognition threshold that a tax position is required to meet before being recognized in the financial statements. The Group recognizes in the financial statements the benefit of a tax position which is ‘‘more likely than not’’ to be sustained under examination based solely on the technical merits of the position assuming a review by tax authorities having all relevant information. Tax positions that meet the recognition threshold are measured using a cumulative probability approach, at the largest amount of tax benefit that has a greater than fifty percent likelihood of being realized upon settlement. It is the Group’s policy to recognize interest and penalties related to unrecognized tax benefits, if any, as a component of income tax expense.

2.23 Borrowings

Borrowings are recognized initially at fair value, net of transaction costs incurred. Borrowings are subsequently stated at amortized cost. Any difference between the proceeds (net of transaction costs) and the redemption value is recognized as interest expense in the consolidated statements of comprehensive loss over the period of the borrowings, using the effective interest method.

2.24 Business combination

The Group accounts for its business combinations using the acquisition method of accounting in accordance with ASC topic 805, Business Combinations (“ASC 805”). The acquisition method of accounting requires all of the following steps: (i) identifying the acquirer, (ii) determining the acquisition date, (iii) recognizing and measuring the identifiable assets acquired, the liabilities assumed, and any noncontrolling interest in the acquiree, and (iv) recognizing and measuring goodwill or a gain from a bargain purchase. The consideration transferred in a business combination is measured as the aggregate of the fair values at the date of exchange of the assets given, liabilities incurred, and equity instruments issued as well as the contingent considerations and all contractual contingencies as of the acquisition date.

The Group allocates the fair value of purchase consideration to the tangible assets acquired, liabilities assumed and intangible assets acquired based on their estimated fair values. The excess of the fair value of purchase consideration over the fair values of these identifiable assets and liabilities is recorded as goodwill. Such valuations require management to make significant estimates and assumptions, especially with respect to intangible assets. Significant estimates in valuing certain intangible assets may include, but are not limited to, future expected cash flows from acquired assets, timing and probability of success of clinical events and regulatory approvals, and assumptions on useful lives of the patents and discount rates. Management’s estimates of fair value are based upon assumptions believed to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates. Additional information, such as that related to income tax and other contingencies, existing as of the acquisition date but unknown to us may become known during the remainder of the measurement period, not to exceed one year from the acquisition date, which may result in changes to the amounts and allocations recorded.

Acquisitions that do not meet the accounting definition of a business combination are accounted for as asset acquisitions. For transactions determined to be asset acquisitions, the Group allocates the total cost of the acquisition, including transaction costs, to the net assets acquired based on their relative fair values.

22

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

2.25 Segment information

In accordance with ASC 280, Segment Reporting, the Group’s chief operating decision maker, the Chief Executive Officer, reviews the consolidated results when making decisions about allocating resources and assessing performance of the Group as a whole and hence, the Group has only one reportable segment. The Group does not distinguish between markets or segments for the purpose of internal reporting. As the Group’s long-lived assets are substantially located in and derived from the PRC, no geographical segments are presented.

2.26 Loss per share

Basic loss per share is computed by dividing net loss attributable to ordinary shareholders by the weighted average number of ordinary shares outstanding during the period using the two-class method. Under the two-class method, the net loss is allocated between ordinary shares and other participating securities based on their participating rights. Net loss is not allocated to other participating securities if based on their contractual terms they are not obligated to share in the loss. Diluted loss per share is calculated by dividing net loss attributable to ordinary shareholders by the weighted average number of ordinary and dilutive ordinary equivalent shares outstanding during the period. Ordinary equivalent shares consist of shares issuable upon the conversion of the preferred shares using the if-converted method, shares issuable upon the issuance of ordinary shares to be issued to Everest using the if-converted method, shares issuable upon the conversion of the convertible promissory notes using the if-converted method, shares issuable upon the exercise of share options using the treasury stock method, shares issuable upon the issuance of ordinary shares for restricted shares units using the treasury stock method, and shares issuable upon the exercise of warrants using the treasury stock method. Ordinary equivalent shares are not included in the denominator of the diluted loss per share calculation when inclusion of such shares would be anti-dilutive.

2.27 Adopted accounting pronouncements

In December 2019, the FASB issued ASU 2019-12 — Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. This ASU provides an exception to the general methodology for calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year. This update also (1) requires an entity to recognize a franchise tax (or similar tax) that is partially based on income as an income-based tax and account for any incremental amount incurred as a non-income-based tax, (2) requires an entity to evaluate when a step-up in the tax basis of goodwill should be considered part of the business combination in which goodwill was originally recognized for accounting purposes and when it should be considered a separate transaction, and (3) requires that an entity reflect the effect of an enacted change in tax laws or rates in the annual effective tax rate computation in the interim period that includes the enactment date. The Group adopted ASU No. 2019-12 from January 1, 2021, which did not have a material impact on the Group’s consolidated financial statements.

In January 2020, the FASB issued Accounting Standards Update No. 2020-01, Investments — Equity Securities (Topic 321), Investments — Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815): Clarifying the Interactions between Topic 321, Topic 323, and Topic 815. The amendments clarified that an entity should consider observable transactions that require it to either apply or discontinue the equity method of accounting for the purposes of applying the measurement alternative in accordance with Topic 321 immediately before applying or upon discontinuing the equity method. The amendments also clarified that for the purpose of applying paragraph 815-10-15-141(a) an entity should not consider whether, upon the settlement of the forward contract or exercise of the purchased option, individually or with existing investments, the underlying securities would be accounted for under the equity method in Topic 323 or the fair value option in accordance with the financial instruments guidance in Topic 825. An entity also would evaluate the remaining characteristics in paragraph 815-10-15-141 to determine the accounting for those forward contracts and purchased options. The Company adopted ASU No. 2020-01 from January 1, 2021, which did not have a material impact on the Group’s consolidated financial statements.

23

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

2. PRINCIPAL ACCOUNTING POLICIES (CONTINUED)

In March 2020, the FASB issued ASU 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting”, which provides optional expedients and exceptions for applying U.S. GAAP on contract modifications and hedge accounting to contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform, if certain criteria are met. These optional expedients and exceptions provided in ASU 2020-04 are effective for the Company as of March 12, 2020 through December 31, 2022. The Company will evaluate transactions or contract modifications occurring as a result of reference rate reform and determine whether to apply the optional guidance on an ongoing basis. The ASU is currently not expected to have a material impact on the Group’s consolidated financial statements.

3. ACCOUNTS RECEIVABLE AND CONTRACT ASSETS

Accounts receivable and contract assets, net of allowance for credit losses, consisted of the following:

No allowance for credit losses was recorded as of December 31, 2020 and June 30, 2021.

24

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

4. PREPAYMENTS AND OTHER RECEIVABLES

5. PROPERTY, EQUIPMENT AND SOFTWARE

Property, equipment and software consist of the following:

The total amounts charged to the consolidated statements of comprehensive loss for depreciation and amortization expenses amounted to approximately RMB5.1 million and RMB6.7 million for the six months ended June 30, 2020 and 2021, respectively.

25

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

6. INTANGIBLE ASSETS

Intangible assets as of December 31, 2020 and June 30, 2021 are summarized as follows:

The three IPR&D assets (TJ103, TJ101, and TJ102) were acquired from the business combination of I-Mab Tianjin and its subsidiaries including Chengdu Tasgen Bio-Tech Co., Ltd. and Shanghai Tianyunjian Bio-Tech Co., Ltd. (together the “Tasgen Group”) in 2017. The licensor of these IPR&D assets was Genexine, Inc. The gross carrying amounts represent the fair value assigned to the respective research and development assets. At the date of acquisition, all three assets had not reached technological feasibility. They were considered indefinite lived.

IPR&D related to TJ103 was subsequently determined to have a finite useful life as a result of an out-licensing arrangement. Consequently, the Group uses the straight-line method to amortize the asset. The amortization for the six months ended June 30, 2020 and 2021 was nil and RMB389, recognized as research and development expenses in the consolidated statements of comprehensive loss, respectively. The estimated amortization expense for each of the five succeeding fiscal years is RMB778.

On September 15, 2020, I-Mab Hong Kong and Genexine, Inc. entered into amendments to Intellectual Property License Agreement with I-Mab Hangzhou to assign and transfer all the rights and obligations related to TJ102 to I-Mab Biopharma (Hangzhou) Limited (“I-Mab Hangzhou”), pursuant to an equity transfer and investment agreement entered into between I-Mab Hong Kong and various parties (see Note 8).

As of December 31, 2020 and June 30, 2021, there was no impairment of the value of the Group’s intangible assets.

26

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

7. GOODWILL

On July 15, 2017, the Group acquired 66.67% of the equity interests in the Tasgen Group by issuing convertible preferred shares, and controlled the board of directors and business of I-Mab Tianjin since then. Tasgen Group is principally engaged in the research and development of innovative medicines and the Group acquired Tasgen Group for its research team, technical experience, and IPR&D pipeline assets (see Note 6). As of December 31, 2020 and June 30, 2021, the goodwill of RMB162,574 represented the goodwill generated from the aforementioned acquisition of Tasgen Group and the business of Tasgen Group was fully integrated into the Company after the acquisition.

As of December 31, 2020 and June 30, 2021, the Group performed a qualitative assessment by evaluating relevant events and circumstances that would affect the Group’s single reporting unit and did not note any indicator that it is more likely than not that the fair value of the Group’s reporting unit is less than its carrying amount and therefore the Group’s goodwill was not impaired.

8. INVESTMENT ACCOUNTED FOR USING THE EQUITY METHOD AND PUT RIGHT LIABILITIES

I-Mab Hangzhou, incorporated on June 16, 2019, was a wholly owned subsidiary of I-Mab Hong Kong with registered capital of US$30 million, which was paid up by I-Mab Hong Kong on September 14, 2020.

On September 15, 2020 (the “Closing Date”), I-Mab Hong Kong entered into an equity transfer and investment agreement (the “SPA”) with (i) a limited partnership jointly established by the management of I-Mab Hangzhou to hold restricted equity of I-Mab Hangzhou issued to the management (“Management Holdco”), (ii) a limited partnership established to hold the shares of I-Mab Hangzhou for future equity incentive plan (“ESOP Holdco”) and (iii) a group of domestic investors in China (“Domestic Investors”).

In accordance with the terms of the SPA,

27

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

8. INVESTMENT ACCOUNTED FOR USING THE EQUITY METHOD AND PUT RIGHT LIABILITIES

(a) Investment accounted for using the equity method (continued)

Upon closing of the SPA, the registered capital of I-Mab Hangzhou remained to be US$30 million. As of December 31, 2020 and June 30, 2021, among the total 25,500,000 outstanding shares of I-Mab Hangzhou, 13,500,000 shares were held by I-Mab Hong Kong while the remaining 12,000,000 shares was held by Domestic Investors. Shares subscribed by Management Holdco and ESOP Holdco, in the total number of 4,500,000, have not yet been purchased by or issued to Management Holdco and ESOP Holdco as of December, 31, 2020 and June 30, 2021. Once all these 4,500,000 subscribed shares of I-Mab Hangzhou are purchased by or issued to Management Holdco and ESOP Holdco, the equity interest in I-Mab Hangzhou held by I-Mab Hong Kong, Domestic Investors, Management Holdco and ESOP Holdco would be 45%, 40%, 10% and 5% respectively.

On the same day, I-Mab Hong Kong also entered into a shareholders agreement with the aforementioned investors (the “SHA”). According to the SHA and I-Mab Hangzhou’s articles of association, the board of directors of I-Mab Hangzhou shall be composed of seven directors. The directors shall be elected in the following ways: I-Mab Hong Kong is entitled to appoint three directors, including the chairman of the board of directors, as well as nominate one independent director; the Management Holdco is entitled to appoint one director; two non-related entities of the Domestic Investors are entitled to appoint one director respectively (“Investors Directors”). Each director of the board of directors shall have one vote. I-Mab Hong Kong, Management Holdco and ESOP Holdco agree to act in concert, as long as each of Management Holdco and ESOP Holdco respectively holds equity in I-Mab Hangzhou, when exercising the rights as a shareholder.

As a result of the above transactions, I-Mab Hangzhou became an affiliate of the Group on the Closing Date in accordance with ASC 810 since I-Mab Hangzhou meets the definition of a business under ASC 805. In accordance with ASC 810-10, I-Mab Hangzhou is a variable interest entity, and no shareholder shall consolidate I-Mab Hangzhou under VIE model as neither party have the power to direct all the activities that most significantly impact the economic performance of I-Mab Hangzhou. Therefore, the Group deconsolidated I-Mab Hangzhou and retained significant influence in I-Mab Hangzhou. The investment was accounted for using the equity method. The retained investment in the common stock of I-Mab Hangzhou was initially measured at fair value in accordance with ASC 810-10-40.

The Group determined the fair value of its retained equity interest with the assistance of an independent third-party valuation firm. The Group used equity allocation model to estimate the fair value of the investment. The fair value as of the Closing Date was US$112,039 (equivalent to approximately RMB764,352), which reflected the fact that the shares subscribed by Management Holdco and ESOP Holdco were not issued and outstanding as of the Closing Date.

A gain of RMB407,598 was recognized as a result of the deconsolidation in September 2020. The gain represented the difference between:

Subsequently, pursuant to the I-Mab Hangzhou’s articles of association, the Group applies the HLBV method to allocate earnings or losses of I-Mab Hangzhou because the liquidation rights and priorities sufficiently differ from what is reflected by the underlying percentage ownership interests. For the six months ended June 30, 2021, the Group recognized RMB83,042 in equity in loss of an affiliate in the consolidated statements of comprehensive loss.

28

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

8. INVESTMENT ACCOUNTED FOR USING THE EQUITY METHOD AND PUT RIGHT LIABILITIES (CONTINUED)

The purchase price of US$3 million committed by Management Holdco under SPA, representing 10% of the equity of I-Mab Hangzhou, is significantly lower than the fair value of the corresponding subscribed shares as of the Closing Date. The excess is considered as share-based compensation to the I-Mab Hangzhou’s management for the services to be used or consumed in the I-Mab Hangzhou’s own operations. The share-based compensation is considered granted upon the Closing Date and cliff vests after five years of service since the Closing Date. Consequently, the Group recognizes its proportionate share of the compensation expense recorded by I-Mab Hangzhou. For the six months ended June 30, 2021, the Group recognized RMB14,164 in equity in loss of an affiliate in the unaudited interim condensed consolidated financial statements of comprehensive loss.

Along with the equity transfer transaction, the team of designated management/workforce transferred from the Group to I-Mab Hangzhou consists of several grantees under the Group’s 2020 Share Incentive Plan (“2020 Plan”, see Note 13(d)). These individuals continued to qualify the definition of the eligible participants under the 2020 Plan after the Closing Date. Meanwhile, there has been no change to any of the award terms. The equity transfer transaction did not trigger the modification accounting to the share-based compensation. Additionally, given that I-Mab Hangzhou became an affiliate to the Group upon deconsolidation, and that the other shareholders of I-Mab Hangzhou are not providing proportionate value to sponsor the 2020 Plan nor is the Group receiving any consideration for the awards granted to employees of I-Mab Hangzhou, the Group is required, under Topic 323, to expense the full costs of share-based compensation as incurred at the same period as the costs are recognized by I-Mab Hangzhou. For the six months ended June 30, 2021, such expenses of RMB12,338 was recorded in the equity in loss of an affiliate in the unaudited interim condensed consolidated financial statements of comprehensive loss.

In March 2021, I-Mab Hangzhou granted stock options to its employees and recognized share-based compensation expenses of RMB4,656 for the six months ended June 30, 2021. Pursuant to the I-Mab Hangzhou’s articles of association, the Group applies the HLBV method to allocate earnings or losses of I-Mab Hangzhou because the liquidation rights and priorities sufficiently differ from what is reflected by the underlying percentage ownership interests. Accordingly, the Group recorded RMB4,656 in the equity in loss of an affiliate in the unaudited interim condensed consolidated financial statements of comprehensive loss for the six months June 30, 2021 and credited additional paid-in capital in the consolidated balance sheet.

29

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

8. INVESTMENT ACCOUNTED FOR USING THE EQUITY METHOD AND PUT RIGHT LIABILITIES (CONTINUED)

(a) Investment accounted for using the equity method (continued)

As of December 31, 2020 and June 30, 2021, the carrying value of the Group’s long-term investment measured under equity method was RMB664,832 and RMB578,030. The Group presented the summarized financial information of the Group’s long-term investment measured under equity method below in accordance with Rule 4-08 of Regulation S-X (RMB in thousands).

30

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

8. INVESTMENT ACCOUNTED FOR USING THE EQUITY METHOD AND PUT RIGHT LIABILITIES (CONTINUED)

Pursuant to the SHA, if I-Mab Hangzhou fails to close a public offering of I-Mab Hangzhou’s shares on the China Stock Exchange’s Science and Technology Innovation Board, Main Board, Small and Medium-Sized Enterprise Board, Growth Enterprise Board, or Hong Kong Stock Exchange, U.S. Stock Exchange, or other stock exchanges approved by the shareholders of I-Mab Hangzhou in accordance with provisions of the SHA within 4 years after September 15, 2020, I-Mab Hong Kong is obligated to repurchase the equity held by Domestic Investors in cash or in I-Mab’s stock (subject to the approval procedures of I-Mab) within 3 years from the expiration of the 4-year period after the Closing Date of September 15, 2020.

The put right written by I-Mab Hong Kong to Domestic Investors is a freestanding equity-linked instrument, which is classified as a put right liability and is initially measured at fair value. Subsequent changes in fair value are recorded in other income (loss) in the consolidated statements of comprehensive income (loss).

The Group determined the fair value of the put right with the assistance of an independent third-party valuation firm. The Group used the option pricing model (finnerty model) to estimate the fair value of the put right using the following assumptions:

The model requires the input of highly subjective assumptions including the expected terms, estimated volatility, spot price and probability of triggering event for redemption option. Expected terms is estimated based on the timing of a hypothetical redemption event which is assumed to be the earlier of expected redemption date or expected public offering date. Expected volatility is estimated based on daily stock prices of the comparable companies for a period with length commensurate to the expected terms of redemption event. The spot price was determined with assistance from an independent third-party valuation firm. The Group’s management is ultimately responsible for the determination of the spot price and probability of triggering event for redemption option.

Significant decreases in interval between valuation date and maturity date, estimated volatility, spot price and probability of triggering event for redemption option would result in a significantly lower fair value measurement.

31

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

9. ACCRUALS AND OTHER PAYABLES

10. ORDINARY SHARES

As of December 31, 2018 and 2019, 500,000,000 ordinary shares had been authorized by the Company. Each ordinary share is entitled to one vote. The holders of ordinary shares are also entitled to receive dividends whenever funds are legally available and when declared by the Board of Directors of the Company.

On October 29, 2019, the Company’s shareholders and board of directors approved that immediately prior to the completion of initial public offering, the Company’s authorized share capital will be changed into US$80,000 divided into 800,000,000 ordinary shares of a par value of US$0.0001 each.

32

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

10. ORDINARY SHARES (CONTINUED)

On January 17, 2020, the Company completed its IPO and became listed on the Nasdaq Global Market by issuing 7,407,400 American Depositary Shares (“ADSs”) at the price of US$14.00 per ADS for total gross proceeds of US$103.7 million. On February 10, 2020, the underwriters of the IPO have exercised their over-allotment option to purchase an additional 768,350 ADSs of the Company at the IPO price of US$14.00 per ADS. After giving effect to the exercise of the over-allotment option, the Company has issued and sold a total of 8,175,750 ADSs in the IPO, for total net proceeds of US$101.3 million (equivalent to RMB697,788), netting of issuance cost from total gross proceeds of US$114.5 million. Each ten ADSs represent twenty-three ordinary shares of the Company.

On January 17, 2020, the Company also issued 6,078,571 ordinary shares to Everest (see Note 14 for details).

Upon the completion of the IPO, the Company’s then outstanding 30,227,056 Series A Preferred Shares, 23,288,783 Series B Preferred Shares, 3,714,580 Series B-1 Preferred Shares, 3,301,849 Series B-2 Preferred Shares, 31,046,360 Series C Preferred Shares and 3,857,143 Series C-1 Preferred Shares were converted into 30,227,056, 23,288,783, 3,714,580, 3,571,427, 34,420,469 and 4,537,814 ordinary shares, respectively.

On July 15, 2020, the Company’s Board of Directors approved a share repurchase program to repurchase in the open market up to US$20 million worth of outstanding ADSs of the Group. The Company made a total prepayment of US$5,000 (equivalent to RMB34,051) for the share repurchase. The prepayment was collected subsequently in October 2020. No repurchase activity was taken place as of June 30, 2021.

On September 3, 2020, the Company entered into definitive subscription agreements with a consortium of institutional investors (the “Investors”) to raise approximately US$418 million through a private placement. The consortium is led by Hillhouse Capital Group (“Hillhouse”), with significant participation by GIC Private Limited, and also includes certain other Asian and U.S. biotech investment funds, Hillhouse is entitled to nominate one representative to I-Mab’s Board of Directors.

The private placement comprises (1) the sale to the Investors of the Group’s 29,133,502 ordinary shares (equivalent to 12,666,740 ADSs) at a purchase price equivalent to US$33 per ADS amounting to approximately US$418 million; and (2) warrants (the “Investor Warrants”, see Note 16(b)) to subscribe for an aggregate of 5,341,267 ordinary shares (equivalent to 2,322,290 ADSs) at an exercise price equivalent to US$45 per ADS, which may further increase the proceeds of approximately US$104.5 million if the Investor Warrants are fully exercised. The Investor Warrants will remain exercisable at the election of the Investors within 12 months after the closing of the private placement. As of June 30, 2021, 4,683,191 warrants were exercised by the Investors. All the remaining warrants were exercised subsequently from July to September 2021.

The subscription agreement with the Hillhouse entities contemplates two closings. The first closing occurred on September 11, 2020, and the second closing is conditioned upon an existing director of the Company having resigned to enable the Hillhouse entities to appoint a director to replace such director and the lemzoparlimab out-licensing agreement with AbbVie (see Note 14) being or remaining effective. Upon the first closing, 20,421,378 ordinary shares and 3,744,032 Investor Warrants were issued to the Investors for total gross proceeds of approximately US$293.0 million. On December 17, 2020, the Group entered into a written amendment made to the subscription agreement with the Hillhouse entities, which removed one of the two conditions for the second closing that an existing director of the Company having resigned to enable the Hillhouse entities to appoint a director to replace such director. The second closing occurred as the other condition was satisfied and 8,712,124 ordinary shares as well as 1,597,235 Investor Warrants were issued to the Hillhouse entities for total gross proceeds of approximately US$125.0 million. The total net proceeds, netting of issuance cost, from the private placement was US$397.2 million (equivalent to RMB2,653,669).

As of June 30, 2021, 5,576,951 stock options were exercised, and 3,713,767 restricted share units were issued as ordinary shares.

33

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

11. CONVERTIBLE PREFERRED SHARES

On October 18, 2016, the Company issued 5,141,587 shares of Series A-1 and A-2 Preferred Shares with a consideration of US$11,282 (equivalent to approximately RMB74,742). In connection with the Series A-1 and A-2 Preferred Shares issuance, the Company also issued 2,246,744 warrant to purchase its Series A-3 Preferred Shares (“Series A-3 Warrants”).

On September 6, 2017, in connection with the Group’s acquisition of Tasgen Group, the Company issued 16,723,646 shares of Series A-3 Preferred Shares at a price of US$2.55 per share with a total consideration of US$42,645 (equivalent to approximately RMB289,024).

Series A-1 Preferred Shares, Series A-2 Preferred Shares and Series A-3 Preferred Shares are also referred to as Series A Preferred Shares.

On September 22, 2017, the Company issued 15,894,594 shares of Series B Preferred Shares with a consideration of US$52,546 (equivalent to approximately RMB346,515). In connection with the Series B Preferred Shares issuance, the Company also issued convertible promissory notes that are convertible into Series B-1 Preferred Shares (“2017 Notes”) and 5,633,780 warrants to purchase its Series B-2 Preferred Shares (“Series B Warrant”).

Concurrently with the Company’s issuance of Series B Preferred Shares, the Company also completed a round of onshore financing with respect to the Group’s subsidiary I-MAB Tianjin (“Series B Onshore Financing”). Series B Onshore Financing comprised 1) capital injection to I-Mab Tianjin by a number of investors (“Series B Onshore Investors”), 2) I-Mab Tianjin’s issuance of convertible loans (“Onshore Convertible Loans” and see Note 14), and 3) the Company’s issuance of 2,620,842 warrants to purchase its Series B-2 Preferred Shares (“Series B Warrants”).

On June 29, 2018, the Company issued total 8,361,823 shares of Series A-3 Preferred Shares upon exercise of Series A-3 Option held by its holder.

On June 29, 2018, the Company issued 2,535,201 shares of Series B-1 Preferred Shares upon conversion of 2017 Notes and issued 2,253,512 shares of Series B-2 Preferred Shares upon exercise of Series B Warrant by Series B preferred shareholders.

On June 29, 2018, the Company issued 5,938,640 shares of Series B Preferred Shares upon exercise of the Series B Option held by a Series B Onshore Investor and issued 947,218 shares of Series B-1 Preferred Shares upon conversion of Onshore Convertible Loans by a Series B Onshore Investor, respectively.

On July 6, 2018, the Company issued 1,455,549 shares of Series B Preferred Shares upon exercise of the Series B Option held by a Series B Onshore Investor, issued 232,161 shares of Series B-1 Preferred Shares upon conversion of Onshore Convertible Loans by a Series B Onshore Investor and issued 1,048,337 shares of Series B-2 Preferred Shares upon exercise of Series B Warrant by Series B Onshore Investors, respectively.

34

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

11. CONVERTIBLE PREFERRED SHARES (CONTINUED)

Series B Preferred Shares, Series B-1 Preferred Shares and Series B-2 Preferred Shares are also referred to as Series B Preferred Shares.

On July 6, 2018, the Company issued 31,046,360 shares of Series C Preferred Shares at a price of US$6.4419 per share with a total consideration of US$200,000 (equivalent to approximately RMB1,323,363). In connection with the offering of the Series C Preferred Shares, the Company incurred issuance costs of RMB16,730.

On July 25, 2019, the Group entered into a share purchase agreement with certain third party investors, under which these investors will subscribe for an aggregate of 3,857,143 Series C-1 convertible preferred shares of the Company for an aggregate purchase price of US$27.0 million. Out of the aforementioned subscription of 3,857,143 Series C-1 convertible preferred shares by certain third party investors, 1,428,571 Series C-1 convertible preferred shares were issued to an investor on October 17, 2019, and the Group also received the cash consideration of US$10,000 (equivalent to approximately RMB70,036). On November 6, 2019, the Group received cash consideration of US$17,000 (equivalent to approximately RMB119,387) for the remaining 2,428,572 Series C-1 convertible preferred shares from the investors and the issuance of such 2,428,572 Series C-1 convertible preferred shares was consummated on that day. In connection with the offering of the Series C-1 convertible preferred shares, the Company incurred issuance costs of approximately US$840 (equivalent to approximately RMB5,887).

Series A Preferred Shares, Series B Preferred Shares, Series C Preferred Shares and Series C-1 Preferred Shares are collectively referred to as Preferred Shares.

Key terms of the Preferred Shares are summarized as follows:

Dividends

The holders of Preferred Shares are entitled to receive dividends, out of any assets legally available therefore, prior and in preference to any declaration or payment of any dividend on the ordinary shares or any other class or series of shares of the Group at the rate of eight percent (8%) of the original issue price per share per annum on each Preferred Share, payable in US$ and annually when, as and if declared by the Board of Directors. Such distributions shall not be cumulative. No dividend, whether in cash, in property or in shares of the capital of the Group, shall be paid on or declared and set aside for any ordinary shares or any other class or series of shares of the Group unless and until all dividends have been paid in full on the Preferred Shares (on an as-converted basis).

Conversion

Each Preferred Share may be converted at any time into ordinary shares at the option of the preferred shares holders at the then applicable conversion price. The initial conversion ratio is 1:1, subject to adjustment in the event of (i) share splits, share combinations, share dividends or distribution, other dividends, recapitalizations and similar events, or (ii) issuance of ordinary shares (excluding certain events such as issuance of ordinary shares pursuant to a public offering) at a price per share less than the conversion price in effect on the date of or immediately prior to such issuance.

35

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

11. CONVERTIBLE PREFERRED SHARES (CONTINUED)

Conversion (continued)

The Preferred Shares shall be automatically converted into ordinary shares immediately upon the closing of a public offering of the Company’s shares with an offering price (exclusive of underwriting commissions and expenses) that reflects a market capitalization (immediately prior to the public offering) of not less than US$1,000,000,000 or otherwise approved by all directors and certain preferred shareholders as specified in the Company’s memorandum and articles of association (the “Qualified Public Offering”).

The Group determined that there were no beneficial conversion features (“BCF”) identified for any of the Preferred Shares during any of the periods. In making this determination, the Company compared the fair value of the ordinary shares into which the Preferred Shares are convertible with the respective effective conversion price at the issuance date. In all instances, the effective conversion price was greater than the fair value of the ordinary shares. To the extent a conversion price adjustment occurs, as described above, the Group will reevaluate whether or not a beneficial conversion feature should be recognized.

Liquidation

In the event of any liquidation (unless waived by the preferred shareholders) including deemed liquidation, dissolution or winding up of the Company, holders of the Preferred Shares shall be entitled to receive a per share amount equal to one hundred percent (100%) of the original issue price on each Preferred Share, plus an amount representing an internal rate of return of twelve percent (12%) per annum on the original issue price as adjusted for share dividends, share splits, combinations, recapitalizations or similar events, plus all accrued and declared but unpaid dividends thereon, in the sequence of Series C Preferred Shares, Series B Preferred Shares and Series A Preferred Shares. After such liquidation amounts have been paid in full, any remaining funds or assets of the Company legally available for distribution to shareholders shall be distributed on a pro rata basis among the holders of the Preferred Shares, on an as-converted basis, together with the holders of the ordinary shares.

Accounting of preferred shares

The Preferred Shares are redeemable by the holders upon a liquidation event, including a deemed liquidation event (e.g., change in control), and as such are presented as mezzanine equity on the consolidated balance sheets. In accordance with ASC 480-10-S99, each issuance of the convertible preferred shares should be recognized at the date of issuance after deducting fair value allocated to the detachable warrants and issuance costs.

Modification of preferred shares

The Company assesses whether an amendment to the terms of its convertible preferred shares is an extinguishment or a modification using the fair value model.

When convertible redeemable preferred shares are extinguished, the difference between the fair value of the consideration transferred to the convertible redeemable Preferred Shareholders and the carrying amount of such preferred shares (net of issuance costs) is treated as a deemed dividend to the Preferred Shareholders. When convertible redeemable preferred shares are modified and such modification results in value transfer between Preferred Shareholders and ordinary shareholders, the change in fair value resulted from the amendment is treated as a deemed dividend to or from the Preferred Shareholders.

36

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

11. CONVERTIBLE PREFERRED SHARES (CONTINUED)

Modification of preferred shares (continued)

On December 25, 2019, the Company’s shareholders and board of directors approved that, where the final offering price of a Qualified Public Offering is no less than US$4.176 per ordinary share, the agreed provisions related to the number of shares to be converted into the Company’s ordinary shares shall apply with respect to the Series C-1 Preferred Shares, Series C Preferred Shares, Series B-2 Preferred Shares and Series B-1 Preferred Shares, which will generally give rise to a one to multiple conversion of the such rounds of Preferred Shares, provided that unanimous consent of the directors on the final offering price needs to be obtained in the event that the final offering price per ordinary share of such IPO is fixed at a price equal to or higher than US$4.176 per ordinary share but lower than US$5.22 per ordinary share.

The Company evaluated the aforementioned modifications and concluded that they represented modifications, rather than extinguishment, to Series B-1, B-2 and C Preferred Shares, which resulted in a transfer of value from ordinary shareholders to preferred shareholders. The combined change in fair value of Series B-1, B-2 and C Preferred Shares immediately before and after the modification was US$4.0 million (equivalent to approximately RMB27.8 million) on December 25, 2019. This decrease in fair value of the ordinary shares of US$4.0 million (equivalent to approximately RMB27.8 million) on December 25, 2019 was, in substance, a transfer of wealth mostly from ordinary shareholders to preferred shareholders, and therefore was recorded as a deemed dividend to the preferred shareholders.

The Company evaluated the aforementioned modifications and concluded that they represented extinguishment to Series C-1 Preferred Shares. The difference between the fair value of the modified Series C-1 Preferred Shares and the carrying value of the original Series C-1 Preferred Shares was amounting US$0.8 million on December 25, 2019 and represented the fair value of the consideration transferred, and therefore was recognized as a deemed dividend to the preferred shareholders and adjustment to the carrying amount of Series C-1 Preferred Shares.

37

I-MAB

Notes to the Unaudited Interim Condensed Consolidated Financial Statements

(All amounts in thousands, except for share and per share data, unless otherwise noted)

11. CONVERTIBLE PREFERRED SHARES (CONTINUED)

The Company’s convertible preferred shares activities for the six months ended June 30, 2020 are summarized below: