Basis of Presentation

The accompanying consolidated financial statements of the Company have been prepared in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”) and in accordance with applicable rules and regulations of the Securities and Exchange Commission ("SEC") for financial reporting.

Use of Estimates

The preparation of Cullinan’s consolidated financial statements and accompanying notes in conformity with U.S. GAAP requires the Company’s management to make estimates and judgments that affect the amounts reported in the financial statements. On an ongoing basis, Cullinan’s management evaluates its estimates, which include, but are not limited to, estimates related to prepaid and accrued research and development expenses, equity-based compensation, income taxes, and the fair value of royalty transfer agreements. Management's estimates could change period to period based on changes in facts and circumstances. The Company’s management bases its estimates on historical experience and on other relevant assumptions that are believed to be reasonable. Actual results may differ materially from these estimates.

Concentration of Risk

Cullinan had no significant concentration of credit risk as of December 31, 2024. Cash and cash equivalents are primarily maintained with three financial institutions in the U.S. as of December 31, 2024. Deposits at banks may exceed the federally insured limits. To date, the Company has not experienced any losses on such accounts. Under our investment policy, the Company limits amounts invested in such securities by investment type, credit rating, maturity, industry group and issuer. The goals of our investment policy are (i) safety and preservation of principal and diversification of risk and (ii) liquidity of investments sufficient to meet cash flow requirements.

Cullinan is subject to certain risks and uncertainties and believes that changes in any of the following areas could have a material adverse effect on future financial position or results of operations: ability to conduct and complete preclinical and clinical trials of our current and future product candidates; ability to obtain future financing; ability to build a successful pipeline of product candidates, including efficient expenditures of its resources; regulatory approval and market acceptance of, and reimbursement for, current and future product candidates; protection of Cullinan’s intellectual property, including litigation or claims against the Company based on intellectual property, patent, product, regulatory or other factors; performance of third-party clinical research organizations and manufacturers upon which the Company relies; and Cullinan’s ability to attract and retain employees necessary to support its growth.

The Company is dependent and expects to continue to be dependent on a small number of third-party manufacturers to supply drug product and drug substance for research and development activities in its programs. These programs could be adversely affected by a significant interruption in supply.

Investments

Cullinan generally holds investments in marketable securities. Investments not classified as cash equivalents with maturities of less than twelve months are classified as short-term investments in the consolidated balance sheets. Investments with maturities greater than twelve months for which the Company has the intent and ability to hold the investment for greater than twelve months are classified as long-term investments in the consolidated balance sheets.

The amortized cost of marketable securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion is included in interest income. Dividends are also included in interest income. Interest receivable is included in prepaid expenses and other current assets on the consolidated balance sheets and represents accrued and unpaid interest on Cullinan's marketable securities. The Company periodically reviews its marketable securities for impairment and adjusts these investments to their fair value when a decline in market value is deemed to be other than temporary. Declines in fair value judged to be other than temporary on marketable securities, if any, are included in other income (expense), net.

Fair Value of Financial Instruments

Cullinan has certain financial assets and liabilities recorded at fair value which have been classified as Level 1, 2 or 3 within the fair value hierarchy as described in the accounting standards for fair value measurements. The three levels of the fair value hierarchy are described below:

Level 1—Unadjusted quoted prices for identical assets or liabilities in active markets that the Company has the ability to access;

Level 2—Quoted prices for similar assets and liabilities in active markets or other market-observable inputs such as interest rates, yield curves and foreign currency spot rates; and

Level 3—Pricing or valuations that require inputs that are both significant to the fair value measurement and unobservable.

There were no transfers of financial assets or liabilities measured at fair value between Level 1 and Level 2, and there were no Level 3 investments during 2024 or 2023.

Cullinan's financial assets recorded at fair value consist of investments. The fair value of the Company’s investments is primarily determined using market quotations or prices obtained from independent pricing sources.

As of December 31, 2024 and 2023, the fair values of cash and cash equivalents, prepaid expenses and other current assets, accounts payable, accrued expenses and other current liabilities approximated their carrying values due to the short-term nature of these instruments.

Property and Equipment, net

Property and equipment is stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over the estimated useful life of each asset as follows:


Asset Class		Estimated Useful Life
Office furniture and equipment		5 years
Leasehold improvements		Shorter of the useful life of the asset or the lease term

Leases

Cullinan determines if an arrangement is a lease at inception. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company classifies leases at the lease commencement date as operating or finance leases and records a right-of-use asset ("ROU") and a lease liability on the consolidated balance sheets for all leases with an initial lease term of greater than 12 months. Leases with an initial term of 12 months or less are not recorded in the balance sheet, and payments are recognized as expense on a straight-line basis over the lease term.

Cullinan enters into contracts that contain both lease and non-lease components. Non-lease components may include maintenance, utilities and other operating costs. The Company combines the lease and non-lease components of fixed costs in its lease arrangements as a single lease component. Variable costs, such as utilities or maintenance costs, are not included in the measurement of ROU assets and lease liabilities but rather are expensed when the event determining the amount of variable consideration to be paid occurs.

Operating lease assets and liabilities are recognized at the lease commencement date based on the present value of the lease payments over the lease term using the discount rate implicit in the lease. If the discount rate is not readily determinable, Cullinan utilizes an estimate of its incremental borrowing rate based upon the available information at the lease commencement date. Operating lease assets are further adjusted for prepaid or accrued lease payments. Operating lease payments are expensed using the straight-line method as an operating expense over the lease term. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that Cullinan will exercise that option.

Impairment of Long-Lived Assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to future undiscounted net cash flows expected to be generated. Impairment charges are recognized at the amount by which the carrying amount of an asset exceeds the fair value of the asset. Assets to be disposed of are reported at the lower of the carrying amount or the fair value less costs to sell.

Noncontrolling Interests

Noncontrolling interests represent third-party interests in the Company’s subsidiaries. Cullinan determines the amount of the noncontrolling interests in the net assets of the Company’s subsidiaries at each balance sheet date using the hypothetical liquidation at book value ("HLBV") method. Under the HLBV method, the amounts reported as noncontrolling interests in the consolidated balance sheets represent the amounts third parties would hypothetically receive at each balance sheet date under the liquidation provisions of the subsidiaries, assuming the net assets of the subsidiaries were liquidated at their recorded amounts determined in accordance with U.S. GAAP and distributed to the owners of the subsidiaries. Net loss attributable to noncontrolling interests on the consolidated statements of operations and comprehensive income (loss) is determined as the difference in the noncontrolling interest in the consolidated balance sheets between the start and end of each reporting period, after taking into account any capital transactions between the subsidiaries and third parties.

Revenue Recognition

Revenue is recognized when a customer obtains control of promised goods or services. The amount of revenue recognized reflects the consideration to which Cullinan expects to be entitled in exchange for these goods and services. To achieve this core principle, the Company applies the following five steps: 1) identify the customer contract; 2) identify the contract’s performance obligations; 3) determine the transaction price; 4) allocate the transaction price to the performance obligations; and 5) recognize revenue when or as a performance obligation is satisfied.

Licensing arrangements are analyzed to determine whether the promised goods or services, which could include licenses and research and development materials and services, are distinct or whether they must be accounted for as part of a combined performance obligation.

The transaction price is determined based on the consideration to which Cullinan will be entitled. The transaction price may include fixed amounts, variable amounts, or both. The Company reevaluates the probability of realizing such variable consideration and any related constraints at each reporting period. Cullinan includes variable consideration in the transaction price to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur.

The Company allocates the transaction price based on the estimated standalone selling price of the underlying performance obligations. Cullinan must develop assumptions that require judgment to determine the standalone selling price for each performance obligation identified in the contract. The Company utilizes key assumptions to determine the standalone selling price, which may include other comparable transactions, pricing considered in negotiating the transaction and the estimated costs to complete the respective performance obligation. Cullinan also utilizes judgment in assessing whether or not variable consideration is constrained or if it can be allocated specifically to one or more performance obligations in the arrangement.

When a performance obligation is satisfied, revenue is recognized for the amount of the transaction price allocated to that performance obligation on a relative standalone selling price basis, which excludes estimates of variable consideration that are constrained. Significant management judgment is required in determining the level of effort required under an arrangement and the period over which the Company is expected to complete its performance obligations under an arrangement.

For performance obligations consisting of licenses and other promises, Cullinan utilizes judgment to assess whether the combined performance obligation is satisfied over time or at a point in time and the recognition pattern for the portion of the transaction price allocated to the performance obligation.

Research and Development Expenses

Research and development costs are expensed as incurred. Research and development expenses consist primarily of employee compensation costs and amounts incurred with third parties for the provision of services for product candidate development, clinical and preclinical development and related supply and manufacturing costs, and regulatory compliance costs. Advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. The prepaid amounts are expensed as the related goods are received or services are performed. At the end of each reporting period, the Company conducts a thorough review of ongoing research and development activities to identify goods received or services rendered in order to establish an estimate of the associated costs incurred. The Company compares payments made to its vendors to its estimate of costs incurred to determine the resulting prepaid or accrual position. Significant judgments and estimates are made in determining the prepaid and accrued balances at the end of any reporting period. Such estimates are subject to change as additional information becomes available, and actual results could differ from the Company’s estimates.

Costs incurred to obtain licenses are recognized as research and development expense if the technology licensed has no alternative future use.

All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses in the consolidated statements of operations and comprehensive income (loss).

Equity-Based Compensation

Equity-based compensation is measured at the grant date for all equity-based awards using the fair value of the awards and is recognized as expense over the requisite service period, which is generally the vesting period. Forfeitures are recognized as they occur. Cullinan classifies equity-based compensation in its consolidated statements of operations and comprehensive income (loss) in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified.

The fair value of service-based restricted stock units ("RSUs") is the closing market price of the Company's common stock on the grant date. The fair value of market-based RSUs is measured on the grant date using a Monte Carlo simulation model. Cullinan estimated the fair value of stock options using the Black-Scholes option pricing model. Both the Monte Carlo simulation model and the Black-Scholes option pricing model require the input of objective and subjective assumptions. Certain assumptions used, including the Company’s expected stock price volatility, involve inherent uncertainties and the application of management’s judgment. As a result, if factors change and management uses different assumptions, equity-based compensation expense could be materially different for future awards.

Income Taxes

Cullinan recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount of benefit that is greater than fifty percent likely to be realized upon settlement. Changes in measurement are reflected in the period in which the change in judgment occurs.

Net Loss per Share Attributable to Cullinan

Cullinan computes net loss per share attributable to Cullinan using the two-class method required for multiple classes of common stock. The Company has determined that the preferred stock does not have preferential rights over the Company’s common stock and, accordingly, is considered to be a second class of common stock for purposes of calculating net loss per share attributable to Cullinan. Basic net loss per share attributable to Cullinan is calculated by dividing the net loss attributable to Cullinan allocated to each share class by the weighted-average number of shares outstanding during the period for that share class. Diluted net loss per share attributable to Cullinan is determined by dividing net loss attributable to Cullinan allocated to each share class by the weighted-average number of shares outstanding during the period for that share class, adjusted for the dilutive effect of shares of common stock equivalents as determined using the treasury stock method for equity awards and the if-converted method for preferred stock.

Recently Adopted Accounting Pronouncements

In November 2023, the Financial Accounting Standards Board (the “FASB”) issued an accounting standards update to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. The main provisions of this update require companies to disclose, on an annual and interim basis, significant segment expenses, segment profit and loss, and other segments items that are regularly provided to the chief operating decision maker ("CODM"). This update also requires companies to disclose the title and position of the CODM and to explain how the CODM uses the reported segment measures in assessing segment performance and deciding how to allocate resources. The update also requires companies with a single reportable segment to provide all required segment reporting disclosures. This new standard will be effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Cullinan adopted this standard on January 1, 2024 for 2024 annual reporting and interim periods beginning in 2025.

Recently Issued Accounting Pronouncements

In December 2023, the FASB issued an accounting standards update to enhance transparency about income tax information through improvements to income tax disclosures primarily related to the rate reconciliation and income taxes paid information. The main provisions in this update will require companies to disclose, on an annual basis, specific categories in the rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold. This update will also require companies to disclose, on an annual basis, the amount of income taxes paid, income (or loss) from continuing operations before income tax expense (or benefit), and income tax expense (or benefit) from continuing operations, disaggregated between federal, state and foreign jurisdictions. This new standard will be effective beginning for fiscal years beginning after December 15, 2024. Cullinan adopted this standard on January 1, 2025.

In November 2024, the FASB issued an accounting standards to improve disclosures regarding the types of expenses included in commonly presented expense captions, including disaggregating the amounts of employee compensation, depreciation and amortization included within each income statement expense caption. This standard is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. Cullinan is evaluating the impact of adopting this ASU on its consolidated financial statements and disclosures.