ILLUMINA, INC.

Reportable Segment Information

As of December 28, 2025, we haveone reportable segment, Core Illumina. Prior to the Spin-Off of GRAIL, on June 24, 2024, our reportable segments included both Core Illumina and GRAIL. See note 8. GRAIL Spin-Off for details. We continue to disclose certain historical information for GRAIL prior to the Spin-Off. Segment information is consistent with how our Chief Operating Decision Maker (CODM), who is our Chief Executive Officer, reviews financial information, makes operating decisions, allocates resources, and assesses performance. We also consider the way budgets and forecasts are prepared and reviewed and the basis on which executive compensation is determined.

Core Illumina: Core Illumina’s products and services serve customers in the research, clinical and applied markets, and enable the adoption of a variety of genomic solutions. Core Illumina sells products and provides services to GRAIL, and vice versa, in accordance with contractual agreements between the entities.

GRAIL: GRAIL is a healthcare company focused on early detection of multiple cancers. Prior to the Spin-Off of GRAIL into a separate, independent public company, GRAIL was required to be held and operated separately and independently from Illumina pursuant to the transitional measures ordered by the European Commission.

Our CODM allocates resources and evaluates business performance based on revenues and net income (loss). Net income (loss) is used in the annual budgeting and monthly forecasting processes and to monitor and assess budgeted/forecasted versus actual results. Our CODM does not evaluate segments using asset information. The accounting policies for segments are the same as those described in the summary of significant accounting policies.

The following tables present selected financial information with respect to segments for the periods presented:

(1)Core Illumina revenue for 2024 and 2023 included intercompany revenue of $15 million and $26 million, respectively.

(2)GRAIL operating expenses are inclusive of cost of revenue, research and development, selling and marketing, general and administrative, and goodwill and intangible impairment for the comparative periods prior to the Spin-Off on June 24, 2024.

Geographic Data

Long-lived assets, consisting of property and equipment and operating lease right-of-use assets, were as follows:

Refer to note 2. Revenue for revenue by geographic area.