Whale Analyzer
Top public holders · 13F and disclosure aggregation

Who owns CIEN? 13F holders and whale ownership

CIEN is tracked across public portfolios in Whale Analyzer. This page answers who owns CIEN, which top funds are buying CIEN, aggregate disclosed value, and recent position changes based on public data. Stephen Mandel is the largest reported holder at $314M; the top five funds control 100.0% of reported ownership; institutions were net selling last quarter (1 increased, 3 reduced). Top tracked holders include Stephen Mandel, Gavin Baker, Whale Rock Capital, and Ray Dalio.

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NYQ · latest quote
$479.50
+$51.28 (+12.0%)
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4Tracked holders
$722.7MAggregate reported value
2026-05-21Page updated
3 reduced, 1 newRecent changes

Top holders

InvestorReported valueSharesChange
Stephen Mandel 13F portfolio
Lone Pine Capital holdings
$314.3M809.5KNew
Gavin Baker 13F portfolio
Atreides Management holdings
$262.8M676.8KReduced
Whale Rock Capital 13F portfolio
Whale Rock Capital Management holdings
$89.8M231.3KReduced
Ray Dalio 13F portfolio
Bridgewater Associates holdings
$55.8M143.8KReduced

Ownership concentration

Reported ownership of CIEN is highly concentrated across tracked institutions.

Whale activity this quarter

Across 4 tracked institutions, 3 reduced, 1 increased. Net positioning is net selling.

Sector positioning — Information Technology

CIEN sits within the Information Technology sector alongside 131 other tracked names. Compare whale ownership across peers:

How to use this page

Values are reported public positions from tracked 13F filers and disclosures — not real-time ownership totals. Open the live CIEN dashboard for price charts and cross-investor scans, or read the SEC 13F guide.

This page is generated from public filings and public disclosures. It is for research and education only and is not investment advice.

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Learn more in Whale Analyzer Academy

Deepen your read on CIEN with these Whale Analyzer Academy guides:

Frequently asked questions

Who owns CIEN stock?

Whale Analyzer tracks 4 public institutional holders of CIEN with a combined reported value of $722.7M. See the holder table above for the largest tracked positions.

Which top funds are buying CIEN?

Tracked institutions were net selling last quarter — 3 reduced, 1 increased. Check the "Change" column: "New" = fresh position, "Increased" = added, "Reduced" = trimmed.

How concentrated is CIEN ownership?

The top five tracked holders report 100.0% of aggregate ownership.

What does 13F ownership mean for CIEN?

Use the interactive CIEN dashboard on Whale Analyzer for real-time holder analysis, or read our 13F Alpha Signals Guide.