10-K – 2026-02-04 – regn-20251231.htm

ASU 2025-06: In September 2025, the FASB issued new guidance to modernize the accounting for software costs by updating the criteria as to when entities are required to start capitalizing internal-use software (by removing all references to software development "projects stages").
January 1, 2028 Early adopted January 1, 2026; no significant impact expected

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2. Product Sales
Net product sales consist of the following:

Year Ended December 31,
(In millions) 2025 2024 2023
EYLEA HD ®
U.S. $ 1,636.9   $ 1,201.1   $ 165.8  
EYLEA ®
U.S. 2,747.8   4,767.1   5,719.6  
Total EYLEA HD and EYLEA U.S.
4,384.7   5,968.2   5,885.4  
Libtayo ®
U.S. 944.7   787.3   538.8  
Libtayo
Rest of world
507.5   429.5   324.3  
Total Libtayo
Global
1,452.2   1,216.8   863.1  
Praluent ®
U.S. 262.5   241.7   182.4  
Evkeeza ®
U.S. 162.2   125.7   77.3  
Inmazeb ®
U.S.
37.4   76.8   69.8  
Other products
Global
10.1   —   —  
$ 6,309.1   $ 7,629.2   $ 7,078.0  

As of December 31, 2025 and 2024, the Company had $ 3.458  billion and $ 4.278  billion, respectively, of trade accounts receivable that were recorded within Accounts receivable, net. As of December 31, 2025 and 2024, two individual customers accounted for 87 % and 79 %, respectively, of the Company's net trade accounts receivable balances.
The Company had product sales to certain customers that each accounted for more than 10% of total gross product revenue for the years ended December 31, 2025, 2024, and 2023. Sales to each of these customers as a percentage of the Company's total gross product revenue are as follows:

Year Ended December 31,
2025 2024 2023
Customer A
50   % 50   % 51   %
Customer B
27   % 24   % 25   %

Revenue from product sales is recorded net of applicable provisions for rebates, chargebacks, and discounts, distribution-related fees, and other sales-related deductions. Accruals for chargebacks and discounts are recorded as a direct reduction to accounts receivable. Accruals for rebates, distribution-related fees, and other sales-related deductions are recorded within accrued liabilities. The following table summarizes the provisions, and credits/payments, for sales-related deductions:

(In millions) Rebates, Chargebacks,
and Discounts Distribution-
Related Fees Other Sales-
Related Deductions Total
Balance as of December 31, 2022
$ 353.9   $ 111.4   $ 81.5   $ 546.8  
Provisions
2,074.5   439.2   155.3   2,669.0  
Credits/payments ( 1,972.7 ) ( 388.3 ) ( 157.5 ) ( 2,518.5 )
Balance as of December 31, 2023
455.7   162.3   79.3   697.3  
Provisions
2,447.3   462.7   143.0   3,053.0  
Credits/payments ( 2,363.9 ) ( 497.2 ) ( 128.8 ) ( 2,989.9 )
Balance as of December 31, 2024
539.1   127.8   93.5   760.4  
Provisions
2,751.7   421.1   119.7   3,292.5  
Credits/payments ( 2,659.2 ) ( 400.7 ) ( 122.2 ) ( 3,182.1 )
Balance as of December 31, 2025
$ 631.6   $ 148.2   $ 91.0   $ 870.8  

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3. Collaboration, License, and Other Agreements
a. Sanofi
The Company is party to a global, strategic collaboration with Sanofi to research, develop, and commercialize fully human monoclonal antibodies, which currently consists of Dupixent ® (dupilumab), Kevzara ® (sarilumab), and itepekimab .
Sanofi is generally responsible for funding 80 % to 100 % of agreed-upon development expenses as incurred. The Company is obligated to reimburse Sanofi for 30 % to 50 % of development expenses that were funded by Sanofi (i.e., "development balance") based on the Company's share of collaboration profits. The Company is required to apply 20 % of its share of profits from the collaboration each calendar quarter to reimburse Sanofi for these development expenses. The Company's contingent reimbursement obligation to Sanofi in connection with the development balance was approximately $ 595 million as of December 31, 2025.
Sanofi leads commercialization activities for products under the collaboration, subject to the Company's right to co-commercialize such products. The Company co-commercializes Dupixent in the United States and in certain countries outside the United States. The Company supplies certain commercial bulk product to Sanofi. The parties equally share profits from sales within the United States. The parties share profits outside the United States on a sliding scale based on sales starting at 65 % (Sanofi)/ 35 % (Regeneron) and ending at 55 % (Sanofi)/ 45 % (Regeneron).
In addition to profit sharing, the Company was entitled to receive sales milestone payments from Sanofi. During the year ended December 31, 2023, the Company earned the final $ 50.0  million sales-based milestone from Sanofi upon aggregate annual sales of antibodies outside the United States exceeding $ 3.0  billion on a rolling twelve-month basis.
Amounts recognized in the Company's Statements of Operations in connection with its Sanofi collaboration are as follows:

Statement of Operations Classification Year Ended December 31,
(In millions) 2025 2024 2023
Regeneron's share of profits Collaboration revenue
$ 5,241.6   $ 3,923.5   $ 3,136.5  
Sales-based milestones earned Collaboration revenue
$ —   $ —   $ 50.0  
Reimbursement for manufacturing of commercial supplies Collaboration revenue
$ 642.4   $ 607.9   $ 613.0  
Regeneron's obligation for its share of Sanofi R&D expenses, net of reimbursement of R&D expenses (R&D expense)
$ ( 69.5 ) $ ( 46.8 ) $ ( 83.7 )
Reimbursement of commercialization-related expenses Reduction of SG&A expense $ 729.3   $ 655.4   $ 534.4  

The following table summarizes contract balances in connection with the Company's Sanofi collaboration:

As of December 31,
(In millions) 2025 2024
Accounts receivable, net $ 1,610.6   $ 1,216.2  
Deferred revenue
$ 442.3   $ 571.7  

b. Bayer
The Company is party to a license and collaboration agreement with Bayer for the global development and commercialization of EYLEA 8 mg (aflibercept 8 mg) and EYLEA (aflibercept) outside the United States. The parties generally share equally agreed-upon development expenses as incurred. The Company is also obligated to use commercially reasonable efforts to supply clinical and commercial bulk product to Bayer.
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Bayer is responsible for commercialization activities outside the United States, and the companies share equally in profits from such sales. Within the United States, the Company is responsible for commercialization and retains profits from such sales. The Company is obligated to reimburse Bayer out of the Company's share of the collaboration profits for 50 % of the agreed-upon development expenses that Bayer has incurred in accordance with a formula based on the amount of development expenses that Bayer has incurred and the Company's share of the collaboration profits, or at a faster rate at the Company's option; the Company's contingent reimbursement obligation to Bayer was approximately $ 296 million as of December 31, 2025.
Amounts recognized in the Company's Statements of Operations in connection with its Bayer collaboration are as follows:

Statement of Operations Classification Year Ended December 31,
(In millions) 2025 2024 2023
Regeneron's share of profits
Collaboration revenue
$ 1,282.7   $ 1,403.3   $ 1,376.4  
Reimbursement for manufacturing of commercial supplies
Collaboration revenue
$ 139.7   $ 95.7   $ 111.1  
Regeneron's obligation for its share of Bayer R&D expenses, net of reimbursement of R&D expenses (R&D expense)
$ ( 20.0 ) $ ( 48.5 ) $ ( 44.0 )

The following table summarizes contract balances in connection with the Company's Bayer collaboration:

As of December 31,
(In millions) 2025 2024
Accounts receivable, net $ 287.6   $ 349.9  
Deferred revenue
$ 295.7   $ 216.3  

c. Other
In addition to the collaboration and license agreements discussed above, the Company has collaboration and license agreements that are not individually significant to its operating results or financial condition at this time. Pursuant to the terms of those agreements, the Company may (i) incur, and/or get reimbursed for, research and development expenses, and/or (ii) be required to pay, and/or may receive, additional amounts contingent upon the occurrence of various future events (e.g., upon the achievement of development and commercial milestones), which in the aggregate could be significant.
In January 2026, the Company's collaboration agreement with Tessera Therapeutics, Inc. to develop and commercialize TSRA-196 (Tessera's investigational program for the treatment of alpha-1 antitrypsin deficiency ("AATD")) became effective. Under the terms of the agreement, the Company made aggregate payments of $ 150.0  million in January 2026, consisting of an up-front payment and the purchase of Tessera preferred stock. The portion related to the up-front payment will be recorded to Acquired IPR&D expense in the first quarter of 2026.
Acquired IPR&D Expenses
During the year ended December 31, 2025, the Company recorded to Acquired IPR&D expense an $ 80.0  million up-front payment in connection with its license agreement with Hansoh Pharmaceuticals Group Company Limited to acquire development and commercial rights outside mainland China, Hong Kong, and Macau for HS-20094 (a dual GLP-1/GIP receptor agonist currently in Phase 3 clinical development in China).
During the year ended December 31, 2024, the Company recorded to Acquired IPR&D expense a $ 45.0  million development milestone in connection with its collaboration agreement with Sonoma Biotherapeutics, Inc.
During the year ended December 31, 2023, the Company recorded to Acquired IPR&D expense a $ 100.0  million development milestone in connection with its collaboration agreement with Alnylam Pharmaceuticals, Inc., a $ 45.0  million up-front payment in connection with its collaboration agreement with Sonoma, and a $ 30.0  million extension payment under its collaboration agreement with Intellia Therapeutics, Inc.
Royalties
The Company has also in-licensed patent and/or technology pursuant to agreements which contain provisions that require the Company to pay royalties, as defined, at rates that range from 0.5 % to 12.5 %, in the event the Company sells or licenses any proprietary products developed under the respective agreements. For the years ended December 31, 2025, 2024, and 2023, the Company recorded royalty expense (net of reimbursements from collaborators, as applicable) of $ 81.3 million, $ 82.9 million, and $ 117.6 million, respectively, based on product sales under various licensing agreements.
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4. Marketable Securities
Marketable securities as of December 31, 2025 and 2024 consist of both available-for-sale debt securities of investment grade issuers (see below and Note 5) as well as equity securities of publicly traded companies (see Note 5).
The following tables summarize the Company's investments in available-for-sale debt securities:

(In millions) Amortized Unrealized Fair
As of December 31, 2025 Cost Basis Gains Losses Value
Corporate bonds $ 10,141.0   $ 80.9   $ ( 2.4 ) $ 10,219.5  
U.S. government and government agency obligations 4,352.2   15.2   ( 0.1 ) 4,367.3  
Commercial paper 540.8   0.3   —   541.1  
Certificates of deposit 265.7   0.2   —   265.9  
Asset-backed securities 241.4   1.4   —   242.8  
Sovereign bonds 76.3   0.5   —   76.8  
$ 15,617.4   $ 98.5   $ ( 2.5 ) $ 15,713.4  

As of December 31, 2024
Corporate bonds $ 8,226.9   $ 25.1   $ ( 31.4 ) $ 8,220.6  
U.S. government and government agency obligations 4,820.5   3.4   ( 6.9 ) 4,817.0  
Commercial paper 548.3   0.4   —   548.7  
Certificates of deposit 380.6   0.5   —   381.1  
Asset-backed securities 279.0   0.6   ( 0.3 ) 279.3  
Sovereign bonds 82.7   0.1   ( 0.4 ) 82.4  
$ 14,338.0   $ 30.1   $ ( 39.0 ) $ 14,329.1  

The Company classifies its investments in available-for-sale debt securities based on their contractual maturity dates. The available-for-sale debt securities as of December 31, 2025 mature at various dates through December 2032. The fair values of available-for-sale debt securities by contractual maturity consist of the following:

As of December 31,
(In millions) 2025 2024
Maturities within one year $ 5,487.1   $ 6,524.3  
Maturities after one year through five years 10,224.8   7,804.8  
Maturities after five years 1.5   —  
$ 15,713.4   $ 14,329.1  

Amounts reclassified from Accumulated other comprehensive income (loss) into Other income (expense), net related to realized gains/losses on sales of available-for-sale debt securities; such amounts were not material for the years ended December 31, 2025, 2024, and 2023.
The Company recognized interest income of $ 716.8 million, $ 711.4 million, and $ 495.9 million for the years ended December 31, 2025, 2024, and 2023, respectively, in Other income (expense), net.
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5. Fair Value Measurements
The table below summarizes the Company's assets and liabilities which are measured at fair value on a recurring basis. The following fair value hierarchy is used to classify assets and liabilities, based on inputs to valuation techniques utilized to measure fair value:
• Level 1 - Quoted prices in active markets for identical assets or liabilities
• Level 2 - Significant other observable inputs, such as quoted market prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, or model-based valuations in which significant inputs used are observable
• Level 3 - Significant other unobservable inputs

(In millions) Fair Value Measurements at Reporting Date
As of December 31, 2025 Fair Value Level 1 Level 2 Level 3

Assets:

Cash equivalents $ 2,121.6   $ 1,127.7   $ 993.9   $ —  
Available-for-sale debt securities:
Corporate bonds 10,219.5   —   10,219.5   —  
U.S. government and government agency obligations 4,367.3   —   4,367.3   —  
Commercial paper 541.1   —   541.1   —  
Certificates of deposit 265.9   —   265.9   —  
Asset-backed securities 242.8   —   242.8   —  
Sovereign bonds 76.8   —   76.8   —  
Equity securities (a)
34.3   34.3   —   —  
Total assets
$ 17,869.3   $ 1,162.0   $ 16,707.3   $ —  

Liabilities:

Contingent consideration
$ 10.3   $ —   $ —   $ 10.3  

As of December 31, 2024
Assets:
Cash equivalents $ 1,452.2   $ 1,264.2   $ 188.0   $ —  
Available-for-sale debt securities:
Corporate bonds 8,220.6   —   8,220.6   —  
U.S. government and government agency obligations 4,817.0   —   4,817.0   —  
Commercial paper 548.7   —   548.7   —  
Certificates of deposit 381.1   —   381.1   —  
Asset-backed securities 279.3   —   279.3   —  
Sovereign bonds 82.4   —   82.4   —  
Equity securities (a)
1,095.3   1,095.3   —   —  
Total assets
$ 16,876.6   $ 2,359.5   $ 14,517.1   $ —  

Liabilities:

Contingent consideration
$ 52.3   $ —   $ —   $ 52.3  

(a) Includes equity securities of $ 33.3 million and $ 43.2 million as of December 31, 2025 and 2024, respectively, that are subject to transfer restrictions expiring in April 2026

In addition to the investments summarized in the table above, the Company classified the following investments within Other noncurrent assets:
• As of December 31, 2025 and 2024, $ 334.0 million and $ 159.8 million, respectively, of equity securities that do not have a readily determinable fair value. The change in carrying value of such investments was a result of additional purchases.
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• As of December 31, 2025 and 2024, equity securities held through ownership interest in an investment fund of $ 147.5 million and $ 52.0 million, respectively, which are measured at fair value based on Level 3 inputs. The change in carrying value was primarily the result of additional purchases by the fund.
Amounts recognized in Other income (expense), net, related to the Company's investments in public equity securities consist of the following:

Year Ended December 31,

(In millions)
2025 2024 2023
Net gains (losses) recognized during the period
$ 955.6   $ 117.7   $ ( 235.6 )
Less: Net gains recognized on investments sold during the period 966.2   —   6.0  
Net unrealized gains (losses) recognized on investments still held as of period end date
$ ( 10.6 ) $ 117.7   $ ( 241.6 )

Other Fair Value Disclosures
The fair value of the Company's long-term debt (see Note 10), which was determined based on Level 2 inputs, was estimated to be $ 1.576 billion and $ 1.484 billion as of December 31, 2025 and 2024, respectively.

6. Inventories
Inventories consist of the following:

As of December 31,
(In millions) 2025 2024
Raw materials $ 641.5   $ 879.5  
Work-in-process 1,641.6   1,342.3  
Finished goods 190.2   139.8  
Deferred costs 727.5   725.7  
$ 3,200.8   $ 3,087.3  

Deferred costs represent the costs of product manufactured and shipped to the Company's collaborators for which recognition of revenue has been deferred. For the years ended December 31, 2025, 2024, and 2023, Cost of goods sold included inventory write-offs and reserves of $ 172.9  million, $ 126.3  million, and $ 102.3  million, respectively.

7. Property, Plant, and Equipment
Property, plant, and equipment, net consists of the following:

As of December 31,
(In millions) 2025 2024
Building and improvements $ 3,105.9   $ 2,573.2  
Leasehold improvements 174.4   154.5  
Laboratory equipment 1,543.7   1,494.5  
Computer equipment and software 522.0   450.8  
Furniture, office equipment, and other
219.7   203.8  
Land 278.8   288.2  
Construction in progress 1,890.2   1,721.6  
7,734.7   6,886.6  
Accumulated depreciation and amortization
( 2,614.3 ) ( 2,286.9 )
$ 5,120.4   $ 4,599.7  

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Property, plant, and equipment in the table above includes leased property under the Company's finance lease at its Tarrytown, New York corporate headquarters. See Note 11.
Depreciation and amortization expense on property, plant, and equipment was $ 364.8 million, $ 354.1 million, and $ 328.8 million for the years ended December 31, 2025, 2024, and 2023, respectively.
As of December 31, 2025 and 2024, $ 4.332  billion and $ 3.884  billion, respectively, of the Company's net property, plant, and equipment was located in the United States and $ 788.0  million and $ 715.9  million, respectively, was located outside the United States (primarily in Ireland).

8. Intangible Assets
Intangible assets, net consist of the following:

As of December 31,
2025 2024
(In millions) Estimated Useful Life Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount
Acquired product rights - Libtayo 13 years $ 1,635.3   $ ( 431.9 ) $ 1,203.4   $ 1,347.7   $ ( 254.3 ) $ 1,093.4  
Other intangibles 8 years 10.0   ( 8.8 ) 1.2   10.0   ( 7.6 ) 2.4  
Acquired in-process research and development
Indefinite
52.8   —  52.8   52.8   —  52.8  
$ 1,698.1   $ ( 440.7 ) $ 1,257.4   $ 1,410.5   $ ( 261.9 ) $ 1,148.6  

During the years ended December 31, 2025 and 2024, the Company recorded additions to the Libtayo intangible asset related to contingent consideration due to Sanofi in connection with the acquisition of worldwide rights to Libtayo in 2022.
Amortization expense on intangible assets was $ 178.8  million, $ 128.9  million, and $ 92.2  million for the years ended December 31, 2025, 2024, and 2023, respectively.
As of December 31, 2025, assuming no changes in the gross carrying amount of intangible assets, amortization expense is estimated to be approximately $ 124  million for each of the years ending December 31, 2026 through December 31, 2030.
In addition to the intangible assets summarized in the table above, during the second quarter of 2025, the Company recorded an indefinite-lived intangible asset in connection with the purchase of a U.S. Food and Drug Administration ("FDA") Rare Pediatric Disease Priority Review Voucher ("PRV") from a third party for $ 155.0  million. During the fourth quarter of 2025, the Company made the decision to utilize the PRV for a regulatory submission, and as a result, the carrying amount was expensed to Research and development.

9. Accrued Expenses and Other Current Liabilities
Accrued expenses and other current liabilities consist of the following:

As of December 31,
(In millions) 2025 2024
Accrued payroll and related costs $ 773.0   $ 640.9  
Accrued clinical expenses 357.2   315.7  
Accrued sales-related costs 875.6   786.2  
Income tax-related costs
351.3   213.2  
Other accrued expenses and liabilities 519.3   571.1  
$ 2,876.4   $ 2,527.1  

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10. Debt
a. Senior Notes
Long-term debt, net of underwriting discounts and offering expenses (which are being amortized as additional interest expense over the period of issuance through maturity), consists of the following:

As of December 31,
(In millions) 2025 2024
1.750 % Senior Notes due September 2030
$ 1,244.5   $ 1,243.3  
2.800 % Senior Notes due September 2050
741.4   741.1  
$ 1,985.9   $ 1,984.4  

Interest on each series of senior notes is payable semi-annually until the applicable maturity dates. Interest expense related to the debt was $ 44.4  million in each of the years ended December 31, 2025, 2024, and 2023.
b. Credit Facility
The Company is party to an agreement with a syndicate of lenders (the "Credit Agreement") which provides for a $ 750.0  million senior unsecured five-year revolving credit facility (the "Credit Facility"). The Credit Agreement includes an option for the Company to elect to increase the commitments under the Credit Facility and/or to enter into one or more tranches of term loans in the aggregate principal amount of up to $ 500.0  million, subject to the consent of the lenders providing the additional commitments or term loans, as applicable, and certain other conditions. The Credit Agreement also provides a $ 50.0  million sublimit for letters of credit.
Proceeds of the loans under the Credit Facility may be used to finance working capital needs, and for general corporate or other lawful purposes, of Regeneron and its subsidiaries. Regeneron Pharmaceuticals, Inc. has guaranteed all obligations under the Credit Facility. The Credit Agreement includes an option for the Company to elect to extend the maturity date of the Credit Facility beyond December 2027, subject to the consent of the extending lenders and certain other conditions.
The Company had no borrowings outstanding under the Credit Facility as of December 31, 2025.
The Credit Agreement contains operating covenants and a maximum total leverage ratio financial covenant. The Company was in compliance with all covenants of the Credit Agreement as of December 31, 2025.

11. Leases
The Company conducts certain of its research, development, and administrative activities at leased facilities. The Company also leases vehicles and other assets.
Tarrytown, New York Corporate Headquarters
The Company leases laboratory and office facilities for its corporate headquarters in Tarrytown, New York (the "Facility") under the Third Amended and Restated Lease and Remedies Agreement (the "Lease") with BA Leasing BSC, LLC, an affiliate of Banc of America Leasing & Capital, LLC ("BAL"), as lessor, and the Third Amended and Restated Participation Agreement (the "Participation Agreement") with Bank of America, N.A., as administrative agent, and a syndicate of lenders (collectively with BAL, the "Participants"), as rent assignees. The Lease, Participation Agreement, and certain related agreements provide for $ 720.0  million of lease financing (previously advanced by the Participants in March 2017 in connection with the acquisition by BAL of the Facility and the Company's lease of the Facility from BAL), which matures when the term of the Lease expires in March 2027, at which time all amounts outstanding thereunder will become payable in full. The Company has the option to further extend the maturity date of the Participation Agreement and the term of the Lease for an additional five-year period, subject to the consent of the Participants and certain other conditions. The Company also has the option to (a) purchase the Facility by paying an amount equal to the outstanding principal amount of the Participants' advances under the Participation Agreement, all accrued and unpaid yield thereon, and all other outstanding amounts under the Participation Agreement, Lease, and certain related documents or (b) sell the Facility to a third party on behalf of BAL.
Pursuant to the Lease, the Company pays all maintenance, insurance, taxes, and other costs arising out of the use of the Facility. The Company is also required to make monthly payments of basic rent to satisfy the yield payable to the Participants on their outstanding advances under the Participation Agreement. Such advances accrue yield at a variable rate per annum based on the one-month forward-looking Secured Overnight Financing Rate ("SOFR") term rate, plus a spread adjustment, plus an applicable margin that varies with the Company's debt rating and total leverage ratio.
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The Lease is classified as a finance lease as the Company has the option to purchase the Facility under terms that make it reasonably certain to be exercised. The agreements governing the Lease financing contain financial and operating covenants. Such financial covenants and certain of the operating covenants are substantially similar to the covenants set forth in the Credit Agreement. The Company was in compliance with all such covenants as of December 31, 2025 .
Aggregate Lease Information
Amounts recognized in the Consolidated Balance Sheet related to the Company's leases are included in the table below.

As of December 31,
(In millions) Classification 2025 2024
Assets:

Finance lease right-of-use assets Property, plant, and equipment, net (a)
$ 576.7   $ 591.2  
Operating lease right-of-use assets
Other noncurrent assets (b)
245.8   217.4  

$ 822.5   $ 808.6  

Liabilities:

Finance lease liabilities - noncurrent
Finance lease liabilities $ 720.0   $ 720.0  
Operating lease liabilities - current
Accrued expenses and other current liabilities
37.8   30.3  
Operating lease liabilities - noncurrent
Other noncurrent liabilities
229.0   204.1  

$ 986.8   $ 954.4  

(a) Finance lease right-of-use assets were recorded net of accumulated amortization of $ 162.9 million and $ 148.4 million as of December 31, 2025 and 2024, respectively

(b) Operating lease right-of-use assets were recorded net of accumulated amortization of $ 68.8 million and $ 78.4 million as of December 31, 2025 and 2024, respectively

Lease costs consist of the following:

Year Ended December 31,
(In millions) 2025 2024 2023
Operating lease costs
$ 35.8   $ 36.5   $ 19.2  
Finance lease costs:

Amortization of finance lease right-of-use assets 14.5   14.5   14.5  
Interest on finance lease liabilities 39.1   46.1   45.0  
Total finance lease costs
53.6   60.6   59.5  

Total lease costs
$ 89.4   $ 97.1   $ 78.7  

Other information related to the Company's leases includes the following:

As of December 31,
2025 2024
Weighted-average remaining lease term (in years):

Finance leases
1.2 2.2
Operating leases
6.9 7.2
Weighted-average discount rate:

Finance leases
4.40 % 5.03 %
Operating leases
5.38 % 5.52 %

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Supplemental cash flow information related to the Company's leases includes the following:

Year Ended December 31,
(In millions) 2025 2024 2023
Cash paid for amounts included in the measurement of operating lease liabilities (included within cash flows from operating activities)
$ 39.6   $ 41.4   $ 22.5  
Right-of-use assets obtained in exchange for operating lease liabilities
$ 59.1   $ 188.1   $ 31.9  

The following is a maturity analysis of the Company's lease liabilities as of December 31, 2025:

(In millions) Finance Leases
Operating Leases
Total

2026 $ 33.7   $ 52.1   $ 85.8  
2027 727.6   52.3   779.9  
2028 —   48.5   48.5  
2029 —   40.3   40.3  
2030 —   31.2   31.2  
Thereafter
—   97.5   97.5  
Total undiscounted lease payments 761.3   321.9   1,083.2  
Imputed interest ( 41.3 ) ( 55.1 ) ( 96.4 )
Total lease liabilities
$ 720.0   $ 266.8   $ 986.8  

12. Stockholders' Equity
The Company's Restated Certificate of Incorporation, as amended, provides for the issuance of up to 40 million shares of Class A Stock, par value $ 0.001 per share, and 320 million shares of Common Stock, par value $ 0.001 per share. Shares of Class A Stock are convertible, at any time, at the option of the holder into shares of Common Stock on a share-for-share basis. Holders of Class A Stock have rights and privileges identical to Common Stockholders except that each share of Class A is entitled to ten votes per share, while each share of Common Stock is entitled to one vote per share. Class A Stock may only be transferred to specified Permitted Transferees, as defined. Under the Company's Restated Certificate of Incorporation, the Company's board of directors is authorized to issue up to 30 million shares of Preferred Stock, in series, with rights, privileges, and qualifications of each series determined by the board of directors.
a. Share Repurchase Programs
The Company's board of directors has authorized share repurchase programs, including a share repurchase program for up to $ 3.0  billion of the Company's Common Stock which was authorized in February 2025. The programs have no time limit and can be discontinued at any time.
The table below summarizes the shares of the Company's Common Stock that the Company repurchased under its share repurchase programs and the cost of such shares, which were recorded as Treasury Stock.

Year Ended December 31,
(In millions) 2025 2024 2023
Number of shares 5.6   2.8   2.9  
Total cost of shares $ 3,456.2   $ 2,613.9   $ 2,214.6  

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As of December 31, 2025, $ 1.486 billion remained available for share repurchases under the Company's share repurchase programs.
b. Dividends
In 2025, the Company's board of directors declared quarterly cash dividends of $ 0.88 per share on its Common Stock and Class A Stock. Each quarterly dividend was paid to the Company's shareholders in the quarter in which the dividend was declared.
Additionally, in January 2026, the Company's board of directors declared a cash dividend of $ 0.94 per share on its Common Stock and Class A Stock. The dividend will be payable to the Company's shareholders in March 2026.

13. Long-Term Incentive Plans
The Company has used long-term incentive plans for the purpose of granting equity awards to employees of the Company, including officers, and non-employee members of the Company's board of directors (collectively, "Participants"). The Participants may receive awards as determined by a committee of independent members of the Company's board of directors or, to the extent authorized by such committee with respect to certain Participants, a duly authorized employee (collectively, the "Committee"). The incentive plan currently used by the Company is the Second Amended and Restated Regeneron Pharmaceuticals, Inc. 2014 Long-Term Incentive Plan (the "Second Amended and Restated 2014 Incentive Plan"). It was most recently adopted and approved by the Company's shareholders in 2020. As of the most recent shareholder approval date, the Second Amended and Restated 2014 Incentive Plan provided for the issuance of up to 22.3 million shares of Common Stock in respect of awards. In addition, upon expiration, forfeiture, surrender, exchange, cancellation, or termination of any award previously granted under the Amended and Restated Regeneron Pharmaceuticals, Inc. 2014 Long-Term Incentive Plan (the "Amended and Restated 2014 Incentive Plan"), the Regeneron Pharmaceuticals, Inc. 2014 Long-Term Incentive Plan (the "Original 2014 Incentive Plan"), or the Second Amended and Restated 2000 Long-Term Incentive Plan (the "2000 Incentive Plan"), any shares subject to such award are added to the pool of shares available for grant under the Second Amended and Restated 2014 Incentive Plan.
The awards that may be made under the Second Amended and Restated 2014 Incentive Plan include: (a) non-qualified stock options and incentive stock options, (b) restricted stock awards, (c) shares of phantom stock (also referred to as restricted stock units, which may be time- or performance-based), and (d) other awards. Any award granted may (but is not required to) be subject to vesting based on the attainment by the Company of performance goals pre-established by the Committee.
Stock option awards grant Participants the right to purchase shares of Common Stock at prices determined by the Committee, with exercise prices that are equal to or greater than the average of the high and low market prices of the Company's Common Stock on the date of grant (the "Market Price"). Options vest over a period of time determined by the Committee, generally on a pro rata basis over a four-year period. The Committee also determines the expiration date of each option. The maximum term of options that have been awarded under the 2000 Incentive Plan, the Original 2014 Incentive Plan, the Amended and Restated 2014 Incentive Plan, and the Second Amended and Restated 2014 Incentive Plan (collectively, the "Incentive Plans") is ten years .
Restricted stock awards grant Participants shares of restricted Common Stock. Such shares are nontransferable for a period determined by the Committee ("vesting period"). Should employment terminate, as specified in the Incentive Plans, except as determined by the Committee in its discretion and subject to the applicable Incentive Plan documents, the ownership of any unvested restricted stock awards will be transferred to the Company.
Phantom stock awards provide the Participant the right to receive Common Stock or an amount of cash based on the value of the Common Stock at a future date. The award is subject to such restrictions, if any, as the Committee may impose at the date of grant or thereafter, including a specified period of employment or the achievement of performance goals. Time-based restricted stock units and performance-based restricted stock units are each a type of phantom stock award permitted under the Second Amended and Restated 2014 Incentive Plan.
The Incentive Plans contain provisions that allow for the Committee to provide for the immediate vesting of awards upon a change in control of the Company, as defined in the Incentive Plans.
As of December 31, 2025, there were 12.4 million shares available for future grants under the Second Amended and Restated 2014 Incentive Plan.
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a. Stock Options
The table below summarizes the activity related to stock option awards under the Company's Incentive Plans during 2025.

Number of Shares
(In millions)
Weighted-Average Exercise Price Weighted-Average Remaining Contractual Term
Intrinsic Value
(In millions)

Outstanding as of December 31, 2024
12.7   $ 588.47  
2025:
Granted 0.7   $ 691.40  
Forfeited ( 0.4 ) $ 752.01  
Exercised ( 1.2 ) $ 519.17  
Outstanding as of December 31, 2025
11.8   $ 596.65   5.7 years
$ 2,185.9  

Vested and expected to vest as of December 31, 2025
11.5   $ 592.93   5.7 years
$ 2,178.9  

Exercisable as of December 31, 2025
8.7   $ 536.47   4.7 years $ 2,100.0  

The Company satisfies stock option exercises with newly issued shares of the Company's Common Stock. The total intrinsic value of stock options exercised during 2025, 2024, and 2023 was $ 193.6 million, $ 1.682  billion, and $ 1.096  billion, respectively. The intrinsic value represents the amount by which the market price of the underlying stock exceeds the exercise price of an option.
The table below summarizes the weighted-average exercise prices and weighted-average grant-date fair values of options granted during the years ended December 31, 2025, 2024, and 2023.

Number of Options Granted
(In millions)
Weighted-Average Exercise Price Weighted-Average Fair Value
2025:
Exercise price equal to Market Price 0.7   $ 691.40   $ 206.58  
2024:
Exercise price equal to Market Price 1.9   $ 786.79   $ 235.32  
2023:
Exercise price equal to Market Price 1.6   $ 835.91   $ 264.37  

For the years ended December 31, 2025, 2024, and 2023, the Company recognized $ 351.9 million, $ 376.0  million, and $ 357.1  million, respectively, of stock-based compensation expense related to stock option awards (net of amounts capitalized as inventory, which were not material for each of the three years). As of December 31, 2025, there was $ 385.8 million of stock-based compensation cost related to unvested stock options, net of estimated forfeitures, which had not yet been recognized. The Company expects to recognize this compensation cost over a weighted-average period of 1.7 years.
Fair Value Assumptions:
The following table summarizes the weighted average values of the assumptions used in computing the fair value of option grants during 2025, 2024, and 2023.

2025 2024 2023
Expected volatility 26   % 25   % 26   %
Expected lives from grant date 5.3 years 5.0 years 5.1 years
Expected dividend yield 0.49   % 0   % 0   %
Risk-free interest rate 3.79   % 4.11   % 4.29   %

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Expected volatility has been estimated based on actual movements in the Company's stock price over the most recent historical periods equivalent to the options' expected lives. Expected lives are principally based on the Company's historical exercise experience with previously issued option grants. Expected dividend yield is based on the Company's historical practice and expectation of future dividend payments. During 2024 and 2023, the expected dividend yield was zero as the Company had not paid dividends nor did it expect to at the time of option grants. The risk-free interest rates are based on quoted U.S. Treasury rates for securities with maturities approximating the options' expected lives.
b. Restricted Stock Awards and Time-Based Restricted Stock Units
A summary of the Company's activity related to restricted stock awards and time-based restricted stock units (excluding performance-based restricted stock units, which are detailed further below) (collectively, "restricted stock") during 2025 is summarized below.

Number of Shares/Units
(In millions)
Weighted-Average Grant
Date Fair Value
Unvested as of December 31, 2024
2.5   $ 760.35  
2025:
Granted 1.4   $ 718.94  
Vested ( 0.7 ) $ 734.49  
Forfeited ( 0.1 ) $ 753.77  
Unvested as of December 31, 2025
3.1   $ 748.08  

For the years ended December 31, 2025, 2024, and 2023, the Company recognized $ 589.8 million, $ 554.7 million, and $ 475.9 million, respectively, of stock-based compensation expense related to restricted stock (net of amounts capitalized as inventory, which were not material for each of the three years). As of December 31, 2025, there was $ 1.493 billion of stock-based compensation cost related to unvested restricted stock which had not yet been recognized. The Company expects to recognize this compensation cost over a weighted-average period of 2.3 years.
c. Performance-based Restricted Stock Units
Performance-based restricted stock units ("PSUs") have been granted to certain members of senior management of the Company. PSUs may be earned based upon the attainment of pre-established performance criteria, which may include a market and/or performance condition. Depending on the terms of the PSUs and the outcome of the pre-established performance criteria, a recipient may ultimately earn the target number of PSUs granted or a specified multiple thereof at the end of a 4 – 6 year vesting period, as applicable.

The table below summarizes activity related to PSUs during 2025. The number of unvested PSUs represents the maximum number of units that are eligible to be earned.

Number of Shares/Units
(In millions)
Weighted-Average Grant
Date Fair Value
Unvested as of December 31, 2024
1.4   $ 247.91  
2025:
Vested ( 1.2 ) $ 209.59  
Unvested as of December 31, 2025
0.2   $ 485.61  

For each of the years ended December 31, 2025, 2024, and 2023 the Company recognized $ 52.0  million of stock-based compensation expense related to PSUs. As of December 31, 2025, there was no stock-based compensation cost expected to be recognized related to unvested PSUs.
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14. Employee Savings Plans
The Company maintains the Regeneron Pharmaceuticals, Inc. 401(k) Savings Plan, as amended and restated (the "Savings Plan"). The terms of the Savings Plan allow U.S. employees (as defined by the Savings Plan) to contribute to the Savings Plan a percentage of their compensation. In addition, the Company may make discretionary contributions, as defined, to the accounts of participants under the Savings Plan. The Company also maintains additional employee savings plans outside the United States, which cover eligible employees.
Expenses recognized by the Company related to contributions to such plans were $ 95.7  million, $ 90.2  million, and $ 84.7  million for the years ended December 31, 2025, 2024, and 2023, respectively.

15. Income Taxes
The Company is subject to U.S. federal, state, and foreign income taxes. Components of income before income taxes consist of the following:

Year Ended December 31,
(In millions) 2025 2024 2023
United States $ ( 476.3 ) $ ( 411.3 ) $ ( 362.3 )
Foreign 5,707.0   5,191.2   4,561.6  
$ 5,230.7   $ 4,779.9   $ 4,199.3  

Components of income tax expense consist of the following:

Year Ended December 31,
(In millions) 2025 2024 2023
Current:
Federal $ 1,012.3   $ 1,092.6   $ 667.9  
State 19.8   ( 11.1 ) 7.7  
Foreign 479.1   43.1   407.9  
Total current tax expense 1,511.2   1,124.6   1,083.5  
Deferred:
Federal ( 845.2 ) ( 935.5 ) ( 834.5 )
State ( 15.5 ) ( 4.9 ) ( 6.5 )
Foreign 75.3   183.1   3.2  
Total deferred tax benefit
( 785.4 ) ( 757.3 ) ( 837.8 )
$ 725.8   $ 367.3   $ 245.7  

Cash paid for income taxes, net of refunds received, by jurisdiction for the year ended December 31, 2025 is as follows:

(In millions) 2025
Federal
$ 576.5  
State
5.3  
Foreign:

Ireland
645.2  
Other
26.0  
$ 1,253.0  

Cash paid for income taxes, net of refunds received, were $ 743.0  million and $ 870.3  million for the years ended December 31, 2024 and 2023, respectively.
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On July 4, 2025, bill H.R. 1, commonly referred to as the "One Big Beautiful Bill Act" or "OBBBA," was signed into law, with certain provisions effective in 2025 and others in 2026. The OBBBA significantly revises U.S. corporate income tax laws by, among other things, restoring the option for immediate expense recognition for U.S.-based research and development expenditures and making permanent the ability to claim first-year bonus depreciation on qualified property. The OBBBA also modifies U.S. taxation on foreign earnings by, among other things, changing the tax rates for Net CFC Tested Income (formerly known as global intangible low-taxed income ("GILTI")) and foreign-derived intangible income (now known as foreign-derived deduction eligible income), modifying the allocation of expenses in calculating foreign tax credits, as well as changing foreign tax credit limitations. As a result of the OBBBA being signed into law, the Company recognized a charge of $ 44.5  million in 2025 related to the re-measurement of the Company's U.S. net deferred tax assets.
A reconciliation of the U.S. federal statutory tax rate to the Company's effective tax rate for the year ended December 31, 2025 is as follows:

2025
(In millions, except percent)
Amount
Percent

U.S. federal statutory tax rate
$ 1,098.4   21.0   %
Foreign tax effects:

Ireland:

Statutory tax rate difference between Ireland and United States
( 480.3 ) ( 9.2 )
Domestic top-up tax
120.0   2.3  
Other
( 5.8 ) ( 0.1 )
Other foreign jurisdictions 7.7   0.1  
Tax credits:

Research and development and orphan drug tax credits ( 133.3 ) ( 2.5 )
Effect of cross-border tax laws:

   Foreign-derived deduction eligible income
( 20.6 ) ( 0.4 )
   Net CFC tested income ("NCTI"), net of foreign tax credit ("FTC")
( 82.7 ) ( 1.6 )
   Subpart F income, net of FTC
8.3   0.1  
Changes in unrecognized tax benefits (a)
124.2   2.4  
Effect of changes in tax laws or rates enacted in the current period 44.5   0.9  
Nontaxable or nondeductible items:

Stock-based compensation
14.1   0.3  
Other permanent differences
27.0   0.5  
Other adjustments
4.3   0.1  
Effective tax rate
$ 725.8   13.9   %

(a) Changes in unrecognized tax benefits for all jurisdictions are aggregated within this category

A reconciliation of the U.S. federal statutory tax rate to the Company's effective tax rate for the years ended December 31, 2024 and 2023 is as follows:

2024 2023
U.S. federal statutory tax rate 21.0   % 21.0   %
Stock-based compensation
( 4.9 ) ( 4.6 )
Taxation of non-U.S. operations
( 4.0 ) ( 6.6 )
Tax credits
( 3.5 ) ( 3.2 )
Foreign-derived deduction eligible income
( 0.8 ) ( 0.3 )
Other permanent differences ( 0.1 ) ( 0.4 )
Effective tax rate 7.7   % 5.9   %

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Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of the Company's deferred tax assets and liabilities are as follows:

As of December 31,
(In millions) 2025 2024
Deferred tax assets:
Capitalized research and development expenses $ 3,146.2   $ 2,530.2  
Deferred compensation 452.0   419.7  
Fixed assets and intangible assets 192.6   145.1  
Accrued expenses 158.8   185.0  
Tax attribute carryforwards 79.6   84.1  
Other 49.9   43.0  
Total deferred tax assets 4,079.1   3,407.1  

Deferred tax liabilities:
Unrealized gains on investments ( 1.9 ) ( 93.0 )
Net deferred tax assets $ 4,077.2   $ 3,314.1  

The Company's federal income tax returns for 2019 through 2024 remain open to examination by the IRS. The Company's 2019 and 2020 federal income tax returns are currently under audit by the IRS. In general, the Company's state income tax returns from 2017 to 2024 remain open to examination. The Company's income tax returns outside the United States remain open to examination from 2020 to 2024. The United States and many states generally have statutes of limitation ranging from 3 to 5 years; however, those statutes could be extended due to the Company's tax credit carryforward position. In general, tax authorities have the ability to review income tax returns in which the statute of limitation has previously expired to adjust the tax credits generated in those years.
The following table reconciles the beginning and ending amounts of unrecognized tax benefits:

(In millions) 2025 2024 2023
Balance as of January 1 $ 1,313.7   $ 696.4   $ 542.8  
Gross increases related to current year tax positions 401.9   353.5   153.4  
Gross (decreases) increases related to prior year tax positions
( 43.1 ) 264.8   3.2  
Gross decreases due to settlements and lapse of statutes of limitations ( 94.6 ) ( 1.0 ) ( 3.0 )
Balance as of December 31 $ 1,577.9   $ 1,313.7   $ 696.4  

In 2025, 2024, and 2023, the increases in unrecognized tax benefits primarily related to the Company's calculation of certain tax credits and other items related to the Company's international operations. In 2025, the Company released liabilities for uncertain tax positions in connection with the settlement of the IRS audit of the Company's 2017 and 2018 federal income tax returns. Interest expense related to unrecognized tax benefits was $ 201.7 million, $ 165.4  million, and $ 77.2  million in 2025, 2024, and 2023, respectively.
The amount of net unrecognized tax benefits that, if settled, would impact the effective tax rate is $ 520.9  million, $ 635.4  million, and $ 442.5  million as of December 31, 2025, 2024, and 2023, respectively.
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16. Legal Matters
From time to time, the Company is a party to legal proceedings in the course of the Company's business. The outcome of any such proceedings, regardless of the merits, is inherently uncertain. If the Company is unable to prevail in one or more of such proceedings, its consolidated financial position, results of operations, and future cash flows may be materially adversely impacted. Costs associated with the Company's involvement in legal proceedings are expensed as incurred. The Company recognizes gain contingencies associated with such proceedings when the award or recovery is realized or realizable and loss contingencies when it is probable that a liability will be incurred and the amount of loss can be reasonably estimated. As of December 31, 2025 and 2024, the Company's accruals for loss contingencies were not material. There are certain loss contingencies that the Company deems reasonably possible for which the possible loss or range of possible loss is not estimable at this time.
a. Proceedings Relating to EYLEA (aflibercept) Injection
(1) United States
As described in greater detail below, the Company has filed several patent infringement lawsuits against various parties in the United States alleging infringement of certain Company patents pertaining to EYLEA, and certain of these patents have also been subject to post-grant proceedings before the United States Patent and Trademark Office ("USPTO").
(i) U.S. Patent Litigation
In 2025, the Company entered into settlement agreements resulting in the dismissal of the previously disclosed patent infringement lawsuits before the United States District Court for the Northern District of West Virginia against Mylan Pharmaceuticals Inc. ("Mylan") and Biocon Biologics Inc. ("Biocon"); Celltrion, Inc. ("Celltrion"); Formycon AG ("Formycon"); and Sandoz Inc. ("Sandoz"). The lawsuits each alleged infringement of certain Company patents, including the Company's U.S. Patent No. 11,084,865 (the "'865 Patent"). Pursuant to the settlement agreements, these parties are precluded from launching their respective aflibercept 2 mg biosimilars until the second half of 2026 (Mylan/Biocon), fourth quarter of 2026 (Sandoz and Formycon), and December 31, 2026 (Celltrion).
On January 10, 2024, the Company filed a patent infringement lawsuit against Amgen Inc. ("Amgen") in the United States District Court for the Central District of California (subsequently transferred to the United States District Court for the Northern District of West Virginia) alleging that Amgen's filing for FDA approval of an aflibercept 2 mg biosimilar infringed certain Company patents. On September 23, 2024, the court denied the Company's motion for a preliminary injunction, which decision was affirmed by the Federal Circuit on March 14, 2025. On June 17, 2025, the Company filed an additional patent infringement lawsuit against Amgen in the United States District Court for the Central District of California alleging that Amgen's continued commercialization of its aflibercept 2 mg biosimilar infringes the Company's U.S. Patent No. 12,331,099. On September 12, 2025, Amgen filed its answer and counterclaims alleging, among other things, that the Company obtained numerous patents fraudulently, rendering them unenforceable, and that obtaining and enforcing certain Company patents violated Section 2 of the Sherman Antitrust Act of 1890, as amended (the "Sherman Antitrust Act"). On November 12, 2025, the Company filed a motion to dismiss Amgen's affirmative defenses and counterclaims.
(ii) Post-Grant Proceedings Before the USPTO
On November 20, 2024, November 29, 2024, and January 15, 2025, Samsung Bioepis, Formycon, and Celltrion, respectively, filed inter partes review ("IPR") petitions in the USPTO against the '865 Patent, each seeking a declaration that the '865 Patent is invalid. On June 6, 2025, the USPTO denied institution of Samsung and Formycon's respective IPR petitions, and on June 25, 2025, the USPTO denied institution of Celltrion's IPR petition.
On July 14, 2025, Fresenius Kabi SwissBioSim GmbH filed IPR petitions in the USPTO against the '865 Patent and U.S. Patent No. 10,828,345 (the "'345 Patent"), seeking a declaration that the '865 Patent and '345 Patent are invalid. On November 20, 2025, and January 6, 2026, the USPTO denied institution of Fresenius' IPR petitions against the '865 Patent and the '345 Patent, respectively.
(2) Outside the United States
As described in greater detail below, the Company has filed patent infringement lawsuits against various parties in several jurisdictions outside the United States alleging infringement of certain Company patents pertaining to EYLEA, and certain of these patents have also been subject to post-grant proceedings before the European Patent Office (the "EPO") and/or other comparable foreign authorities.
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(i) Multijurisdictional Settlements
Biocon . On December 13, 2025, the Company and Bayer entered into a settlement agreement with Biocon and its affiliated entities in respect of all jurisdictions outside the United States with the exception of Canada (separately settled in March 2024, as previously disclosed). Pursuant to the settlement agreement, all pending judicial and administrative proceedings related to Biocon's aflibercept 2 mg biosimilar product has been dismissed and Biocon is permitted to launch such biosimilar product in the United Kingdom in January 2026 and in the rest of the jurisdictions covered by the settlement in March 2026 or, in each case, earlier in certain circumstances.
Celltrion . On January 21, 2026, the Company and Bayer entered into a settlement agreement with Celltrion in respect of all jurisdictions outside the United States with the exceptions of Canada (separately settled in July 2024, as previously disclosed) and Singapore (separately settled in November 2025). Pursuant to the settlement agreement, all pending judicial and administrative proceedings related to Celltrion's aflibercept 2 mg biosimilar product, including the previously disclosed litigation in South Korea, has or will be dismissed and Celltrion is permitted to launch such biosimilar product in South Korea and the United Kingdom in January 2026 and in the rest of the jurisdictions covered by the settlement in the second quarter of 2026, or earlier in certain circumstances.
Alvotech . On January 28, 2026, the Company and Bayer entered into a settlement agreement with Alvotech HF ("Alvotech") in respect of all jurisdictions outside the United States. Pursuant to the settlement agreement, all pending judicial and administrative proceedings related to Alvotech's aflibercept 2 mg biosimilar product, including the litigation in Germany discussed below, has or will be dismissed and Alvotech is permitted to launch such biosimilar product in Canada, the United Kingdom, and Japan in January 2026 (November 2026 in the case of the DME indication in Japan) and in the rest of the jurisdictions covered by the settlement in May 2026.
Samsung Bioepis . On January 29, 2026, the Company and Bayer entered into a settlement agreement with Samsung Bioepis in respect of all jurisdictions outside the United States with the exception of Canada (separately settled in October 2024, as previously disclosed). Pursuant to the settlement agreement, all pending judicial and administrative proceedings related to Samsung Bioepis' aflibercept 2 mg biosimilar product, including the litigation in the United Kingdom, Germany, the Netherlands, and South Korea discussed below, has or will be dismissed and Samsung Bioepis is permitted to maintain its biosimilar on the market in South Korea and launch such biosimilar product in the United Kingdom in January 2026, the rest of Europe in April 2026, and the rest of the jurisdictions covered by the settlement in May 2026.
(ii) Europe
(I) EPO Post-Grant Proceedings
Various parties, including Amgen and other, anonymous parties, are seeking revocation of the Company's European Patent Nos. 2,944,306 (the "'306 Patent"), 3,716,992 (the "'992 Patent"), and 3,384,049 (the "'049 Patent") before the Opposition Division ("OD") of the EPO. On November 26, 2024, following an oral hearing, the OD announced its decision to revoke the '306 Patent. On March 11, 2025, the Company appealed the OD's decision, and an oral hearing concerning the appeal has been scheduled for October 2026. On October 22, 2025, following an oral hearing, the OD upheld the validity of the '992 Patent's claims in amended form. An oral hearing concerning the '049 Patent has been scheduled for April 2026.
(II) Country-Specific Proceedings
The Company is also party to proceedings against various parties, including Samsung Bioepis, Formycon, Amgen, Alvotech, Celltrion, Sandoz, and/or their affiliated entities, before several European national courts (including those in Belgium, France, Germany, Italy, the Netherlands, and the United Kingdom). In certain of these proceedings, the counterparties are seeking revocation of one or more Company patents pertaining to EYLEA, including the '306 Patent, the '992 Patent, the Company's European Patent No. 2,364,691 (the "'691 Patent"), and the Company's European Patent No. 1,183,353 (as extended by Supplementary Protection Certificate 2013C/029), and/or a declaration that their respective aflibercept 2 mg biosimilars would not infringe these patents, and in the same or other proceedings, the Company is alleging infringement of such patents. As noted above, the Company and Bayer recently entered into settlement agreements with Samsung Bioepis, Alvotech, and Celltrion, pursuant to which the proceedings discussed below have been or will be dismissed with respect to these parties. Key recent developments in the proceedings set forth below are as follows:
• United Kingdom :
◦ Following trials held in June 2025, the High Court of England and Wales issued a decision in October 2025 that found that Formycon and Samsung Bioepis's aflibercept 2 mg biosimilar products do not infringe the '691 and '306 Patents; upheld the '691 Patent as valid; and invalidated the '306 Patent. In December 2025, the Company appealed this decision.
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◦ Proceedings in the United Kingdom concerning the '992 Patent are stayed pending resolution of the EPO proceedings concerning this patent.
• Germany :
◦ Following a June 2025 trial concerning the revocation proceeding brought by Samsung Bioepis, the German Federal Patent Court upheld the '691 Patent as valid.
◦ In October 2025, the Munich Regional Court issued a decision that found that Formycon's aflibercept biosimilar product infringes the '691 Patent and granted the Company's motion for a permanent injunction, enjoining Formycon from selling its aflibercept 2 mg biosimilar in Germany and several other EU countries (including Spain and the Netherlands) until the expiration of the '691 Patent.
◦ In January 2026, the Munich Regional Court issued decisions that found that each of Alvotech's, Celltrion's, and Sandoz's aflibercept 2 mg biosimilar products infringes the '691 Patent and granted the Company's motions for preliminary injunctions, enjoining such parties from selling their aflibercept 2 mg biosimilars in Germany and, in the case of Alvotech, also several other EU countries (including France, Spain, Italy, and the Netherlands).
• Netherlands :
◦ Following a trial held in July 2025, the District Court of the Hague issued a decision in October 2025 that upheld the '691 and '306 Patents as valid; found that Samsung Bioepis's aflibercept 2 mg biosimilar product infringes the '691 and '306 Patents; and granted the Company's request for a permanent injunction, enjoining Samsung Bioepis from selling its aflibercept 2 mg biosimilar in the Netherlands until the expiration of the '691 and '306 Patents.
(iii) Canada
In 2025, the Company, Bayer Inc., and Bayer Healthcare LLC entered into settlement agreements resulting in the dismissal of the previously disclosed patent infringement lawsuits and/or invalidation proceedings before the Federal Court of Canada against Amgen Canada Inc. ("Amgen Canada") and Sandoz Canada Inc. Pursuant to the settlement agreements, the Company, Bayer Inc., and Bayer Healthcare LLC are no longer seeking a declaration that Amgen Canada's or Sandoz's respective aflibercept 2 mg biosimilar products infringe the asserted Company patents.
(iv) South Korea
As noted above, the Company and Bayer recently entered into settlement agreements with Samsung Bioepis and Celltrion, pursuant to which the proceedings discussed below have been or will be dismissed with respect to these parties.
On December 13, 2022, Samsung Bioepis initiated invalidation proceedings before the Intellectual Property Trial and Appeal Board of the Korean Intellectual Property Office ("KIPO") against the Company's Korean Patent No. 1406811 (the "'811 Patent"), seeking revocation of the '811 Patent in its entirety. On October 23, 2024, the KIPO maintained the '811 Patent as valid. On October 30, 2025, the IP High Court overturned the decision of the KIPO and invalidated the '811 Patent; the Company has appealed that decision.
The Company and, as applicable, Bayer Consumer Care AG, have also filed patent infringement lawsuits in the Seoul Central District Court against various parties including Samsung Bioepis and its parent company Samsung Biologics Co., Ltd. (collectively, "Samsung"), Sam Chun Dang Pharm. Co., Ltd. and OPTUS Pharmaceutical Co., Ltd., and Celltrion. These lawsuits seek damages and/or injunctive relief and allege that the making, constructing, using, or selling of an aflibercept 2 mg biosimilar by the relevant defendant(s) would infringe one or more claims of the '811 Patent and/or the Company's Korean Patent Nos. 659477 (the "'477 Patent") and 2519234 (the "'234 Patent"). On February 7, 2025, the Seoul Central District Court granted the Company's preliminary injunction request against Samsung on the basis of the '811 Patent. Also on February 7, 2025, the Seoul Central District Court denied Regeneron's preliminary injunction request against Celltrion. In light of the decision of the IP High Court discussed above, on December 3, 2025, the Seoul High Court issued a decision lifting the preliminary injunction against Samsung.
(v) Australia
On June 4, 2025, the Company, Bayer Consumer Care AG, and Bayer Australia filed a patent infringement lawsuit against Sandoz Pty Ltd. and a request for a preliminary injunction in the Federal Court of Australia alleging that the importing, selling, supplying, or otherwise disposing of an aflibercept 2 mg biosimilar would infringe one or more claims of the Company's Australian Patent No. 2012205599. On September 3, 2025, the court denied the Company's request for a preliminary injunction. On November 26, 2025, the parties entered into a settlement agreement, pursuant to which this lawsuit has been dismissed.
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(vi) Japan
On October 10, 2025, the Company filed a patent infringement lawsuit in the Osaka District Court against Fuji Pharma Co., Ltd. alleging that the making, constructing, using, or selling of an aflibercept 2 mg biosimilar by the defendant would infringe one or more claims of the Company's Japanese Patent No. 7,733,706.
b. Proceedings Relating to EYLEA (aflibercept) Injection Pre-filled Syringe
On July 17, 2020, the Company filed an antitrust lawsuit (as amended on January 25, 2021) against Novartis Pharma AG, Novartis Pharmaceuticals Corporation, and Novartis Technology LLC (collectively, "Novartis") and Vetter Pharma International GmbH in the United States District Court for the Southern District of New York seeking a judgment that the defendants' conduct relating to Novartis's attempt to assert its U.S. Patent No. 9,220,631 against Regeneron in 2020 violated Sections 1 and 2 of the Sherman Antitrust Act, and constituted tortious interference with contract. The Company is also seeking injunctive relief and treble damages. On September 21, 2021, this lawsuit was transferred to the Northern District of New York. On June 10, 2022, the Company filed an appeal of the District Court's decision to dismiss the amended complaint with the U.S. Court of Appeals for the Second Circuit (the "Second Circuit"). On March 18, 2024, the Second Circuit reversed the District Court's decision to dismiss the amended complaint and remanded the lawsuit to the District Court for further proceedings consistent with the Second Circuit's opinion. On November 19, 2024, the Company moved to transfer the lawsuit back to the Southern District of New York, which motion was granted on December 5, 2024.
c. Proceedings Relating to Praluent (alirocumab) Injection
On May 27, 2022, the Company filed a lawsuit against Amgen in the United States District Court for the District of Delaware, alleging that, beginning in 2020, Amgen engaged in an anticompetitive bundling scheme which was designed to exclude Praluent from the market in violation of federal and state laws. The lawsuit seeks damages for harm caused by the alleged scheme, as well as injunctive relief restraining Amgen from continuing its alleged anticompetitive conduct. A trial was held in May 2025. On May 15, 2025, the jury reached a verdict in Regeneron's favor on nine of the ten counts submitted to it and awarded Regeneron $ 135.6 million in compensatory damages and $ 271.2 million in punitive damages. On June 20, 2025, Amgen filed a post-trial motion for judgment as a matter of law or, in the alternative, for a new trial. Also on June 20, 2025, the Company filed a post-trial motion for (i) permanent injunctive relief, (ii) a constructive trust, and (iii) prejudgment interest. An oral hearing on Amgen's and Regeneron's respective post-trial motions was held on August 27, 2025.
d. Department of Justice Matters
On June 24, 2020, the U.S. Attorney's Office for the District of Massachusetts filed a civil complaint in the U.S. District Court for the District of Massachusetts alleging violations of the federal Anti-Kickback Statute and asserting causes of action under the federal False Claims Act and state law (the "June 2020 Civil Complaint") relating to the Company's support of 501(c)(3) organizations that provide financial assistance to patients. On September 27, 2023, the court (i) denied in part and granted in part the Company's motion for summary judgment and (ii) denied in its entirety the motion for partial summary judgment filed by the U.S. Attorney's Office for the District of Massachusetts. On October 25, 2023, the court certified for interlocutory appeal a portion of the court's September 27, 2023 order that addressed the causation standard applicable to the alleged violations of the federal Anti-Kickback Statute and federal False Claims Act. On February 18, 2025, the U.S. Court of Appeals for the First Circuit affirmed the portion of the court's September 27, 2023 order that had been certified for interlocutory appeal. On October 1, 2025, the U.S. Attorney's Office for the District of Massachusetts filed a second motion for partial summary judgment.
On June 3, 2021, the United States District Court for the Central District of California unsealed a qui tam complaint (as amended on October 29, 2021) filed against the Company, Regeneron Healthcare Solutions, Inc., and Sanofi-Aventis U.S. LLC by two qui tam plaintiffs (known as relators) purportedly on behalf of the United States and various states (the "State Plaintiffs"). The amended complaint alleges violations of the federal Anti-Kickback Statute and asserts causes of action under the federal False Claims Act and state law relating to allegedly unlawful remuneration and assistance provided to prescribers. Also on June 3, 2021, the United States and the State Plaintiffs notified the court of their decision to decline to intervene in the case. On January 14, 2022, the Company filed a motion to dismiss the amended complaint in its entirety. On July 25, 2023, the court granted in part and denied in part the Company's motion to dismiss. On September 1, 2023, the Company filed a second motion to dismiss the amended complaint or, in the alternative, a motion for judgment on the pleadings. On July 31, 2024 and August 15, 2024, respectively, the District Court granted the Company's second motion to dismiss the amended complaint with respect to the remaining causes of action under federal law and declined to exercise supplemental jurisdiction over the remaining causes of action under state law. On August 26, 2024, the qui tam plaintiffs filed a notice of appeal. Oral argument on the appeal was held on November 18, 2025.
In June 2021, the Company received a civil investigative demand ("CID") from the U.S. Department of Justice pursuant to the federal False Claims Act relating to, among other things, alleged inflated reimbursement rates for EYLEA by excluding
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applicable discounts, rebates, and benefits from the average sales price reported to the Centers for Medicare & Medicaid Services. On March 28, 2024, the U.S. District Court for the District of Massachusetts unsealed a qui tam complaint against the Company and others by two qui tam plaintiffs, purportedly on behalf of the United States and various states and municipalities, asserting causes of action under the federal False Claims Act and state and local laws, and alleging violations of the federal Anti-Kickback statute related to, among other things, the alleged conduct described above. Also on March 28, 2024, the U.S. Department of Justice and the U.S. Attorney's Office for the District of Massachusetts filed a civil complaint in partial intervention (the "March 2024 Civil Complaint") of the qui tam action, in the same court, asserting causes of action under the federal False Claims Act and a claim for unjust enrichment related to the alleged conduct described above. On June 25, 2024, the States of Colorado, Georgia, Michigan, North Carolina, Texas, and Washington filed a civil complaint in partial intervention (the "June 2024 Civil Complaint") in the same court asserting causes of action under various state laws related to the same alleged conduct. On April 29, 2025, the court denied the Company's motion to dismiss the March 2024 Civil Complaint and the June 2024 Civil Complaint. On June 18, 2025, the States of Maine, Nebraska, Ohio, Oregon, and Wyoming intervened in the action and filed a consolidated complaint asserting causes of action under their respective state laws.
e. Proceedings Initiated by Other Payors
The Company is party to several lawsuits relating to the conduct alleged in the June 2020 Civil Complaint discussed under "d. Department of Justice Matters" above. These lawsuits were filed by UnitedHealthcare Insurance Company and United Healthcare Services, Inc. (collectively, "UHC") and Humana Inc. ("Humana") in the United States District Court for the Southern District of New York on December 17, 2020 and July 22, 2021, respectively; and by Blue Cross and Blue Shield of Massachusetts, Inc. and Blue Cross and Blue Shield of Massachusetts HMO Blue, Inc. (collectively, "BCBS"), Medical Mutual of Ohio ("MMO"), Horizon Healthcare Services, Inc. d/b/a Horizon Blue Cross Blue Shield of New Jersey ("Horizon"), and Local 464A United Food and Commercial Workers Union Welfare Service Benefit Fund ("Local 464A") in the U.S. District Court for the District of Massachusetts on December 20, 2021, February 23, 2022, April 4, 2022, and June 17, 2022, respectively. These lawsuits allege causes of action under state law and the federal Racketeer Influenced and Corrupt Organizations Act ("RICO") and seek monetary damages and equitable relief. The MMO and Local 464A lawsuits are putative class action lawsuits. On December 29, 2021, the lawsuits filed by UHC and Humana were stayed by the United States District Court for the Southern District of New York pending resolution of the proceedings before the U.S. District Court for the District of Massachusetts concerning the allegations in the June 2020 Civil Complaint. On September 27, 2022, the lawsuits filed by BCBS, MMO, and Horizon were stayed by the U.S. District Court for the District of Massachusetts pending resolution of the proceedings before the same court concerning the allegations in the June 2020 Civil Complaint; and, in light of these stays, the parties to the Local 464A action have also agreed to stay that matter.
On June 24, 2024, a group of plaintiffs purporting to be assignees of claims by various Medicare Advantage plans and related entities filed a putative class action complaint in the U.S. District Court for the District of Columbia on behalf of Medicare Advantage plans and other payors. The lawsuit relates to the conduct alleged in the June 2020 Civil Complaint, March 2024 Civil Complaint, and June 2024 Civil Complaint discussed under "d. Department of Justice Matters" above. The lawsuit alleges causes of action under state law and RICO and seeks monetary damages and equitable relief. On October 22, 2024, the Company filed a motion to transfer the proceedings to the U.S. District Court for the District of Massachusetts or, in the alternative, to stay the proceedings or dismiss the proceedings. On January 28, 2025, pursuant to a stipulation among the parties, the proceedings were transferred to the U.S. District Court for the District of Massachusetts. On February 1, 2025, the parties jointly filed a stipulation to stay the action pending resolution of the proceedings before the same court concerning the allegations in the June 2020 Civil Complaint.
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f. Shareholder Derivative Complaint – Department of Justice June 2020 Civil Complaint Matters
On June 29, 2021, an alleged shareholder filed a shareholder derivative complaint in the New York Supreme Court, naming the then-current and certain former members of the Company's board of directors and certain then-current and former executive officers of the Company as defendants and Regeneron as a nominal defendant. The complaint asserts that the individual defendants breached their fiduciary duties in relation to the allegations in the June 2020 Civil Complaint discussed under "d. Department of Justice Matters" above. The complaint seeks an award of damages allegedly sustained by the Company; an order requiring Regeneron to take all necessary actions to reform and improve its corporate governance and internal procedures; disgorgement from the individual defendants of all profits and benefits obtained by them resulting from their sales of Regeneron stock; and costs and disbursements of the action, including attorneys' fees. On July 28, 2021, the defendants filed a notice of removal, removing the case from the New York Supreme Court to the U.S. District Court for the Southern District of New York. On September 23, 2021, the plaintiff moved to remand the case to the New York Supreme Court. Also on September 23, 2021, the individual defendants moved to dismiss the complaint in its entirety. On December 19, 2022, the U.S. District Court for the Southern District of New York denied the plaintiff's motion to remand the case and granted a motion to stay the case pending resolution of the proceedings before the U.S. District Court for the District of Massachusetts concerning the allegations in the June 2020 Civil Complaint. As a result of the stay, the court also terminated the Company's motion to dismiss the complaint without prejudice. The Company can therefore renew the motion to dismiss upon conclusion of the stay.
g. Shareholder Derivative Complaints – Department of Justice March 2024 Civil Complaint Matters
In 2025, various purported shareholders of the Company filed several shareholder derivative complaints in the U.S. District Court for the Southern District of New York or the Supreme Court of the State of New York against members of the Company's board of directors and certain current and former executive officers of the Company as defendants and Regeneron as a nominal defendant. The complaints allege that the individual defendants, among other things, breached their fiduciary duties to the Company by failing to properly manage and oversee the Company in connection with the conduct alleged in the March 2024 Civil Complaint discussed under "d. Department of Justice Matters" above, and one lawsuit also alleges a breach of fiduciary duty relating to the conduct alleged in the second amended putative class action civil complaint discussed under "i. Class Action Civil Complaint" below. The complaints also allege that the individual defendants breached the federal securities laws, wasted corporate assets, and unjustly enriched themselves at the expense of the Company. The complaints seek, among other things, an award of damages allegedly sustained by the Company as a result of the alleged misconduct of the individual defendants; an order requiring the individual defendants to take all necessary actions to reform and improve the Company's corporate governance and internal procedures; and costs and disbursements of the applicable action, including attorneys' fees. Certain of these shareholder derivative complaints have been consolidated by the U.S. District Court for the Southern District of New York. The shareholder derivative complaints filed in the Supreme Court of the State of New York have been removed to the U.S. District Court for the Southern District of New York and motions to remand are pending.
h. Shareholder Derivative Complaint – Director Compensation
On July 22, 2025, an alleged shareholder filed a shareholder derivative complaint in the New York Supreme Court, naming the current non-employee members of our board of directors, and the co-Chairs of our board of directors (who also serve as our President and Chief Executive Officer and our President and Chief Scientific Officer, respectively) as defendants and Regeneron as a nominal defendant. The complaint asserts that the individual defendants breached their fiduciary duties and/or were unjustly enriched when they approved and/or received allegedly excessive non-employee director compensation in 2024 and 2025, and that this allegedly excessive compensation was a waste of corporate assets. The complaint seeks damages in favor of Regeneron for the alleged breaches of fiduciary duties, unjust enrichment, and waste of corporate assets; improvements to Regeneron's corporate governance and internal procedures; equitable relief, including restitution from the individual defendants; and award of the costs of the action, including attorneys' fees. On September 25, 2025, the Company filed a motion to dismiss the complaint.
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i. Class Action Civil Complaint
On January 7, 2025 (as amended on September 8, 2025 and October 30, 2025), a purported shareholder filed a putative class action civil complaint, on behalf of himself and all others similarly situated, in the U.S. District Court for the Southern District of New York against the Company and certain current and former executive officers of the Company. The second amended complaint asserts violations of federal securities laws in connection with statements or disclosures purportedly related to the conduct alleged in the March 2024 Civil Complaint discussed under "d. Department of Justice Matters" above as well as allegations relating to the launch of EYLEA HD. On July 10, 2025, the court appointed a lead plaintiff and lead counsel for the action. On November 17, 2025, the Company filed a motion to dismiss the second amended complaint.
j. Sanofi Litigation
On November 18, 2024, the Company filed a lawsuit (as amended on December 20, 2024) in the United States District Court for the Southern District of New York against Sanofi and certain of its affiliated entities. The lawsuit alleges that the defendants breached certain provisions of the parties' Amended and Restated License and Collaboration Agreement, dated as of November 10, 2009 (as amended, the "Collaboration Agreement"), concerning Sanofi's obligation to provide Regeneron with full access to material information relating to the commercialization of Dupixent or other products commercialized pursuant to the Collaboration Agreement and Regeneron's audit rights under the Collaboration Agreement. The lawsuit seeks a declaratory judgment, injunctive relief, damages, and other relief. On July 3, 2025, Sanofi filed a motion to dismiss the complaint.

17. Net Income Per Share
The calculations of basic and diluted net income per share are as follows:

Year Ended December 31,

(In millions, except per share data) 2025 2024 2023
Net income - basic and diluted $ 4,504.9   $ 4,412.6   $ 3,953.6  

Weighted average shares - basic 104.6   107.9   106.7  
Effect of dilutive securities:
Stock options 1.9   4.8   4.9  
Restricted stock awards and restricted stock units 2.1   2.4   2.1  
Weighted average shares - diluted 108.6   115.1   113.7  

Net income per share - basic $ 43.07   $ 40.90   $ 37.05  
Net income per share - diluted $ 41.48   $ 38.34   $ 34.77  

Shares which have been excluded from diluted per share amounts because their effect would have been antidilutive include the following:

Year Ended December 31,

(Shares in millions) 2025 2024 2023
Stock options 6.2   1.6   1.8  
Restricted stock awards and restricted stock units
0.2   —   —  

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18. Statement of Cash Flows
The following provides a reconciliation of cash, cash equivalents, and restricted cash reported within the Consolidated Balance Sheets to the total of the same such amounts shown in the Consolidated Statements of Cash Flows:

December 31,
(In millions) 2025 2024 2023
Cash and cash equivalents $ 3,118.1   $ 2,488.2   $ 2,730.0  
Restricted cash included in Other current assets
5.6   0.8   —  
Restricted cash included in Other noncurrent assets
—   —   7.8  
Total cash, cash equivalents, and restricted cash shown in the Consolidated Statements of Cash Flows
$ 3,123.7   $ 2,489.0   $ 2,737.8  

Restricted cash consists of amounts held pursuant to contractual arrangements and for dividends payable on certain equity awards.
Supplemental disclosure of non-cash investing and financing activities

As of December 31,
(In millions) 2025 2024 2023
Accrued capital expenditures $ 178.8   $ 151.6   $ 75.4  
Accrued contingent consideration in connection with acquisitions
$ 58.9   $ 62.7   $ 71.6  

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19. Segment Information
The Company operates in one business segment, which includes all activities related to the discovery, development, and commercialization of medicines for serious diseases. The determination of a single business segment is consistent with the consolidated financial information regularly provided to the Company's chief operating decision maker ("CODM"). The Company's CODM is its Chief Executive Officer, who reviews and evaluates consolidated net income for purposes of assessing performance, making operating decisions, allocating resources, and planning and forecasting for future periods.
In addition to the significant expense categories included within consolidated net income presented on the Company's Consolidated Statements of Operations, see below for disaggregated amounts that comprise research and development expenses:

Year Ended December 31,
(In millions) 2025 2024
2023

Direct research and development expenses (a)
$ 1,758.1   $ 1,588.8   $ 1,295.6  

Indirect research and development expenses:

Payroll and benefits 1,800.8   1,681.7   1,537.0  
Lab supplies and other research and development costs
258.2   241.5   210.6  
Occupancy and other operating costs 635.4   614.9   518.2  
Total indirect research and development expenses
2,694.4   2,538.1   2,265.8  

Clinical manufacturing costs
1,391.2   1,195.9   1,053.9  

Priority review voucher
155.0   —   —  

Reimbursement of research and development expenses by collaborators ( 148.5 ) ( 190.8 ) ( 176.3 )

Total research and development expenses
$ 5,850.2   $ 5,132.0   $ 4,439.0  

(a) Direct research and development expenses are comprised primarily of costs paid to third parties for clinical and product development activities, and the portion of research and development expenses incurred by our collaborators that we are obligated to reimburse

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