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 benefits1,800.8 1,681.7 1,537.0 
Lab supplies and other research and development costs
258.2 241.5 210.6 
Occupancy and other operating costs635.4 614.9 518.2 
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

About Segments Disclosures

Segment disclosures break a company into its reportable operating units, revealing revenue, profit, and asset allocation that consolidated financial statements obscure. Under ASC 280, segments must match how the chief operating decision maker views the business, providing a window into internal management structure and resource allocation priorities.

Key signals: compare segment margins to identify which units drive profitability and which destroy value. Watch for changes in the number of reportable segments — segment aggregation or disaggregation often coincides with strategic shifts or attempts to obscure declining performance. Intersegment elimination patterns reveal internal pricing practices. The reconciliation between segment totals and consolidated figures exposes corporate overhead allocation and unallocated items. Geographic revenue concentration highlights regulatory and currency exposure. Compare segment-level capital expenditure against segment revenue to assess where management is investing for future growth versus harvesting existing assets.