Telecom Equipment Stocks Surge 7% Ahead of S&P 500 Reentry Fueled by AI Data Center Boom

Ciena Corp. (NYSE: CIEN), the U.S.-based optical communications equipment provider, closed at $289.46 per share on the New York Stock Exchange, up 6.78% from the previous session—equivalent to roughly ₩420,000. Trading volume totaled 2.23 million shares, and the company’s market capitalization rose by about $2.97 billion (approximately ₩4.3 trillion) in a single day, bringing total market value to roughly $40.8 billion (around ₩60 trillion).

Driven by a surge in demand for high-capacity optical networks in AI data centers, Ciena’s share price jumped more than 170% in 2025 alone. On February 9, before the market opened, S&P Dow Jones announced that Ciena would join the S&P 500 index—replacing Diebold Nixdorf, which was removed due to acquisition—marking Ciena’s return to the benchmark after 17 years. The move is expected to attract additional passive and institutional inflows.

Headquartered in Hanover, Maryland, Ciena supplies optical transport systems and network-control software to global telecom carriers and cloud providers. With annual revenues of about $4.8 billion and major customers including AT&T, Verizon, and Meta, the company has emerged as a key beneficiary of ultra-high-speed optical links between data centers—an infrastructure critical to AI expansion.