ILLUMINA, INC.

As of September 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. 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 following tables present selected financial information with respect to segments for the periods presented:

(1)Core Illumina revenue included intercompany revenue of $15 million in YTD 2024.

(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 period prior to the Spin-Off on June 24, 2024.

MANAGEMENT’S DISCUSSION & ANALYSIS

Our Management’s Discussion and Analysis (MD&A) is designed to help readers understand our results of operations, financial condition, and cash flow. It is provided in addition to the accompanying condensed consolidated financial statements and notes. This MD&A is organized as follows:

•Management’s Overview and Outlook. High level discussion of our operating results and significant known trends that affect our business.

•Results of Operations. Discussion of our revenues and expenses.

•Liquidity and Capital Resources. Discussion of key aspects of our condensed consolidated statements of cash flows, changes in our financial position, and our financial commitments.

•Critical Accounting Policies and Estimates. Discussion of significant changes since our most recent Annual Report on Form 10-K that we believe are important to understanding the assumptions and judgments underlying our condensed consolidated financial statements.

•Recent Accounting Pronouncements. Summary of recent accounting pronouncements applicable to our condensed consolidated financial statements.

•Quantitative and Qualitative Disclosure About Market Risk. Discussion of our financial instruments’ exposure to market risk.

Our discussion of our results of operations, financial condition, and cash flow for Q3 2024 and YTD 2024 can be found in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” within our filing of Form 10-Q for the fiscal quarter ended September 29, 2024.

This MD&A discussion contains forward-looking statements that involve risks and uncertainties. See Consideration Regarding Forward-Looking Statements preceding the Condensed Consolidated Financial Statements section of this report for additional factors relating to such statements. This MD&A should be read in conjunction with our condensed consolidated financial statements and accompanying notes included in this report and our Annual Report on Form 10-K for the fiscal year ended December 29, 2024. Operating results are not necessarily indicative of results that may occur in future periods.