Ciena Rejoins S&P 500 After Seventeen Years

Networking hardware maker Ciena will rejoin the S&P 500, returning to the benchmark on Wednesday after being removed in 2009, S&P Dow Jones Indices said. The company, whose market cap nearly tripled over the past year, replaces Dayforce following its $12.3 billion acquisition; about 18% of fiscal 2025 revenue came from an unnamed cloud provider and 11% from AT&T. Inclusion reflects rising demand for data-center infrastructure tied to generative AI and supports Ciena's forecasted ~24% fiscal 2026 revenue growth.