Lumentum Holdings, the photonics and optical technology company trading under the ticker LITE, is being added to the Nasdaq-100 Index effective May 18, 2026. It replaces CoStar Group in the index that tracks the 100 largest non-financial companies listed on the Nasdaq exchange.
The inclusion caps one of the more remarkable growth stories in the semiconductor-adjacent space. LITE shares have surged between 145% and 150% year-to-date in 2026, building on a 339% gain in 2025. The company's market capitalization now sits at roughly $70 billion, dwarfing CoStar Group's $13 billion valuation.
The company specializes in photonic and optical technologies, components essential for high-bandwidth networks required by AI workloads. As hyperscale cloud providers race to build infrastructure for large language models, Lumentum's product portfolio has become critical.
Nasdaq announced the index change on May 8, 2026, and LITE shares ticked up 1.2% intraday on the news. This follows the company's addition to the S&P 500 on March 23, 2026.
Index inclusion creates structural demand as ETFs and index funds tracking the benchmark must buy shares. For passive investors holding broad market funds, Lumentum's inclusion means automatic exposure to the stock.