BlackRock, Inc. ownership in CIE1 / Ciena Corporation

Ciena Corporation

DE ˙ XTRA ˙ US1717793095

446,00 € ↓ -115,00 (-20,50%)

2026-06-04
DEL PRIS

Security	DE:CIE1 / Ciena Corporation
Institution	BlackRock, Inc.
Latest Disclosed Ownership	11,274,540 shares
Ownership	8.00%

2026-04-24 - BlackRock, Inc. has filed an SCHEDULE 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 11,274,540 shares of Ciena Corporation (DE:CIE1). This represents 8.0 percent ownership of the company. In their previous filing dated 2025-12-04 , BlackRock, Inc. had reported owning 14,537,914 shares, indicating a decrease of -22.45 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File Date	Effective Date	Form	Prev Shares	Latest Shares	ΔShares (Percent)	Ownership (Percent)	ΔOwnership (Percent)
2026-04-24	2026-04-24	13G/A	14,537,914	11,274,540	-22.45	8.00	-22.33
2025-12-04	2025-12-04	13G/A	13,392,861	14,537,914	8.55	10.30	9.57
2025-04-17	2025-04-17	13G/A	16,296,261	13,392,861	-17.82	9.40	-16.81
2024-01-30	2024-01-30	13G/A	17,139,924	16,296,261	-4.92	11.30	-1.74
2023-01-26	2023-01-26	13G/A	17,139,924	17,139,924	0.00	11.50	0.00
2023-01-20	2023-01-20	13G	15,514,375	17,139,924	10.48	11.50	15.00
2022-01-27	2022-01-27	13G/A	15,514,375	15,514,375	0.00	10.00	0.00
2022-01-26	2022-01-26	13G/A	15,877,338	15,514,375	-2.29	10.00	-1.96
2021-04-12	2021-04-12	13G/A	15,877,338	15,877,338	0.00	10.20	0.00
2021-04-12	2021-04-12	13G/A	14,792,049	15,877,338	7.34	10.20	6.25
2021-01-29	2021-01-29	13G/A	14,792,049	14,792,049	0.00	9.60	0.00
2021-01-29	2021-01-29	13G/A	15,698,042	14,792,049	-5.77	9.60	-5.88
2020-02-04	2020-02-04	13G/A	17,899,503	15,698,042	-12.30	10.20	-10.53
2019-01-30	2019-01-30	13G/A	17,899,503	17,899,503	0.00	11.40	0.00
2019-01-24	2019-01-24	13G/A	15,147,611	17,899,503	18.17	11.40	8.57
2018-01-19	2018-01-19	13G/A	15,164,642	15,147,611	-0.11	10.50	-2.78
2017-01-12	2017-01-12	13G/A	14,119,594	15,164,642	7.40	10.80	6.93
2016-10-07	2016-10-07	13G/A	11,260,485	14,119,594	25.39	10.10	21.69
2016-02-10	2016-02-10	13G/A		11,260,485		8.30
2015-01-23	2015-01-23	13G/A		8,945,792		8.40
2014-02-10	2014-02-10	13G/A		9,575,753		9.20
2013-01-11	2013-01-11	13G/A		10,144,450		10.08
2012-09-10	2012-09-10	13G/A		10,204,707		10.18
2012-02-13	2012-02-13	13G/A		6,678,034		6.85

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel Premium Registration Required .

Disclosed Equity Positions (from 13F/NPORT Filings)

File Date	Effective Date	Form	Security	Class	ID	Reported Shares	ΔShares	ΔShares (%)	Reported Value (x1000)	ΔValue (%)	Alloc (%)
2026-05-13	2026-03-31	13F	CIENA	COM NEW	171779309	13,373,787	-3,295,043	-19.77	5,192,105	33.19	0.0907
2026-02-12	2025-12-31	13F	CIENA	COM NEW	171779309	16,668,830	1,072,719	6.88	3,898,339	71.59	0.0659
2025-11-12	2025-09-30	13F	CIENA	COM NEW	171779309	15,596,111	-1,471,087	-8.62	2,271,885	63.67	0.0398
2025-08-12	2025-06-30	13F	CIENA	COM NEW	171779309	17,067,198	27,897	0.16	1,388,075	34.81	0.0264
2025-05-02	2025-03-31	13F	CIENA	COM NEW	171779309	17,039,301	-62,339	-0.36	1,029,685	-29.01	0.0216
2025-02-07	2024-12-31	13F	CIENA	COM NEW	171779309	17,101,640	950,030	5.88	1,450,390	45.80	0.0293
2024-11-13	2024-09-30	13F	CIENA	COM NEW	171779309	16,151,610	541,840	3.47	994,778	32.27	0.0209
2024-08-13	2024-06-30	13F	CIENA	COM NEW	171779309	15,609,770	230,877	1.50	752,079	-1.11	0.0170
2024-05-10	2024-03-31	13F	CIENA	COM NEW	171779309	15,378,893	-917,300	-5.63	760,486	3.68	0.0177
2024-02-13	2023-12-31	13F	CIENA	COM NEW	171779309	16,296,193	124,653	0.77	733,492	-4.03	0.0187
2023-11-13	2023-09-30	13F	CIENA	COM NEW	171779309	16,171,540	-479,131	-2.88	764,267	8.03	0.0220
2023-08-11	2023-06-30	13F	CIENA	COM NEW	171779309	16,650,671	-246,129	-1.46	707,487	-20.28	0.0195
2023-05-12	2023-03-31	13F	CIENA	COM NEW	171779309	16,896,800	-243,490	-1.42	887,420	1.56	0.0262
2023-02-13	2022-12-31	13F	CIENA	COM NEW	171779309	17,140,290	312,931	1.86	873,812	28.44	0.0274
2022-11-14	2022-09-30	13F	CIENA	COM NEW	171779309	16,827,359	933,250	5.87	680,330	-6.34	0.0231
2022-08-12	2022-06-30	13F	CIENA	COM NEW	171779309	15,894,109	-12,816	-0.08	726,360	-24.69	0.0233
2022-05-12	2022-03-31	13F	CIENA	COM NEW	171779309	15,906,925	392,550	2.53	964,436	-19.24	0.0260
2022-02-10	2021-12-31	13F	CIENA	COM NEW	171779309	15,514,375	241,846	1.58	1,194,141	52.27	0.0304
2021-11-09	2021-09-30	13F	CIENA	COM NEW	171779309	15,272,529	-22,923	-0.15	784,244	-9.87	0.0220
2021-08-11	2021-06-30	13F	CIENA	COM NEW	171779309	15,295,452	-581,886	-3.66	870,159	0.16	0.0242
2021-05-07	2021-03-31	13F	CIENA	COM NEW	171779309	15,877,338	1,085,289	7.34	868,808	11.13	0.0255
2021-02-05	2020-12-31	13F	CIENA	COM NEW	171779309	14,792,049	1,206,685	8.88	781,761	44.98	0.0249
2020-11-06	2020-09-30	13F	CIENA	COM NEW	171779309	13,585,364	-712,829	-4.99	539,205	-30.37	0.0199
2020-08-14	2020-06-30	13F	CIENA	COM NEW	171779309	14,298,193	-402,653	-2.74	774,390	32.32	0.0309
2020-05-01	2020-03-31	13F	CIENA	COM NEW	171779309	14,700,846	-997,196	-6.35	585,241	-12.67	0.0286
2020-02-13	2019-12-31	13F	CIENA	COM NEW	171779309	15,698,042	-77,060	-0.49	670,150	8.29	0.0257
2019-11-08	2019-09-30	13F	CIENA	COM NEW	171779309	15,775,102	258,661	1.67	618,856	-3.03	0.0260
2019-08-22	2019-06-30	13F/A-1	CIENA	COM NEW	171779309	15,516,441	-2,565,548	-14.19	638,189	-5.48	0.0273
2019-08-13	2019-06-30	13F	CIENA	COM NEW	171779309	15,516,441	-2,565,548		638,189
2019-05-09	2019-03-31	13F	CIENA	COM NEW	171779309	18,081,989	182,486	1.02	675,180	11.24	0.0301
2019-02-08	2018-12-31	13F	CIENA	COM NEW	171779309	17,899,503	1,561,445	9.56	606,974	18.92	0.0306
2018-11-09	2018-09-30	13F	CIENA	COM NEW	171779309	16,338,058	115,012	0.71	510,400	18.68	0.0221
2018-08-09	2018-06-30	13F	CIENA	COM NEW	171779309	16,223,046	678,436	4.36	430,072	6.82	0.0198
2018-05-09	2018-03-31	13F	CIENA	COM NEW	171779309	15,544,610	396,999	2.62	402,605	26.99	0.0192
2018-02-09	2017-12-31	13F	CIENA	COM NEW	171779309	15,147,611	-322,800	-2.09	317,037	-6.72	0.0151
2017-11-14	2017-09-30	13F	CIENA	COM NEW	171779309	15,470,411	143,935	0.94	339,884	-11.37	0.0171
2017-08-10	2017-06-30	13F	CIENA	COM NEW	171779309	15,326,476	-428,724	-2.72	383,470	3.09	0.0203
2017-05-12	2017-03-31	13F	CIENA	COM NEW	171779309	15,755,200	15,622,062	11,733.74	371,979	11,349.03	0.0204
2017-02-10	2016-12-31	13F	CIENA	COM NEW	171779309	133,138	-29,731	-18.25	3,249	-8.48	0.0046
2016-11-08	2016-09-30	13F	CIENA	COM NEW	171779309	162,869	40,249	32.82	3,550	54.41	0.0051
2016-08-10	2016-06-30	13F	CIENA	COM NEW	171779309	122,620	-12,583	-9.31	2,299	-10.58	0.0035
2016-05-10	2016-03-31	13F	CIENA	COM NEW	171779309	135,203	90,396	201.75	2,571	177.35	0.0041
2016-02-11	2015-12-31	13F	CIENA	COM NEW	171779309	44,807	2,102	4.92	927	4.63	0.0014
2015-11-13	2015-09-30	13F	CIENA	COM NEW	171779309	42,705	3,493	8.91	886	-4.63	0.0014
2015-08-07	2015-06-30	13F	CIENA	COM NEW	171779309	39,212	3,518	9.86	929	34.83	0.0014
2015-05-13	2015-03-31	13F	CIENA	COM NEW	171779309	35,694	32,584	1,047.72	689	1,029.51	0.0010
2015-02-09	2014-12-31	13F	CIENA	COM NEW	171779309	3,110	0	0.00	61	17.31	0.0001
2014-10-29	2014-09-30	13F	CIENA	COM NEW	171779309	3,110	0	0.00	52	-22.39	0.0001
2014-08-06	2014-06-30	13F	CIENA	COM NEW	171779309	3,110	-127	-3.92	67	-8.22	0.0001
2014-05-02	2014-03-31	13F	CIENA	COM NEW	171779309	3,237	-8,228	-71.77	73	-73.36	0.0001
2014-02-12	2013-12-31	13F	CIENA	COM NEW	171779309	11,465	1,788	18.48	274	12.76	0.0004
2013-11-12	2013-09-30	13F	CIENA	COM NEW	171779309	9,677	-116	-1.18	243	27.23	0.0005
2013-08-13	2013-06-30	13F	CIENA	COM NEW	171779309	9,793	9,793		191		0.0004

Legend

Shares: The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value: The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price: The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class: This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred

Allocation (%): The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation: The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%): The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis: The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss: This is the market value of the position as of the effective date minus the cost basis.