Illumina Shares Plummets 3.7 as $350M Trading Volume Surges 92% to Rank 421st Amid Margin Expansion and Share Buybacks

Illumina (ILMN) fell 3.70% on July 31, 2025, with a trading volume of $350 million, up 92.78% from the prior day, ranking 421st in market activity. The stock’s performance coincided with the release of its Q2 2025 financial results, which showed $1.06 billion in revenue, a 3% decline year-over-year. Despite the revenue contraction, the company reported GAAP operating margins of 20.2% and non-GAAP margins of 23.8%, reflecting margin expansion. Free cash flow totaled $204 million, and the firm repurchased 4.5 million shares for $380 million at $84.66 apiece.

Illumina revised its full-year guidance, narrowing its revenue decline forecast to 0.5%-2.5% from 1%-3% previously. Non-GAAP diluted EPS guidance was raised to $4.45-$4.55, up from $4.20-$4.30, citing tax benefits from new U.S. R&D incentives. The company also announced a $380 million acquisition of SomaLogic from Standard BioTools, expected to close in mid-2026. Management highlighted operational efficiency in clinical segments and cost management in research amid funding constraints.

Financially, Illumina ended the quarter with $1.16 billion in cash and investments. Gross margin dipped to 65.6% due to higher freight costs and intangible asset impairments, while R&D expenses rose slightly. The acquisition of SomaLogic aligns with its strategy to expand proteomics capabilities. CEO Jacob Thaysen emphasized progress in X consumables and clinical growth as key drivers for future performance.

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