← All S&P 500 additions
CIEN — S&P 500 index addition
Ciena
Sector
Unknown
Announced
Feb 9, 2026
Effective
Feb 9, 2026
Replaced
Dayforce
1W after inclusion
+4.9%
+5.2% vs S&P 500
1M after inclusion
+17.4%
+19.7% vs S&P 500
3M after inclusion
+89.2%
+83.3% vs S&P 500
6M after inclusion
+42.4%
+32.3% vs S&P 500
1Y after inclusion
—
window not elapsed
Indexed performance around the effective date (effective close = 100)
Prices last updated: 2026-09-16 06:30 UTC (9h ago)
Run-up in the 30 days into inclusion: +25.6%
Other stocks added to the S&P 500
- RDDT — Reddit joined on Aug 18, 2026.
- FERG — Ferguson Enterprises joined on Aug 5, 2026.
- HONA — Honeywell Aerospace joined on Jun 29, 2026.
- FLEX — Flex Ltd. joined on Jun 22, 2026.
- MRVL — Marvell Technology joined on Jun 22, 2026.
- FDXF — FedEx Freight joined on Jun 1, 2026.
See the full S&P 500 additions log or the index review calendar.