CTKB Cytek Biosciences, Inc.

NASDAQ
$4.81

Cytek Biosciences, Inc. (CTKB) Institutional Ownership

What the institutions did with CTKB last quarter, from their 13F filings. Counting managers rather than shares is the point: a single index fund adding to a position tells you far less than four hundred separate managers all deciding to. Positions as reported for the quarter ended June 30, 2026.

Managers reporting
190
filed a 13F this quarter
Managers holding
153
-9 on the quarter
Buyers
73
28 opened new
Sellers
101
37 sold out entirely
Buyer share
42.0%
of managers who traded it
Breadth
-16.1
net buyers, as a share of those trading

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Largest holders

Manager Shares % of reported
BlackRock, Inc. 9.6M 11.8%
MILLENNIUM MANAGEMENT LLC 9.3M 11.5%
Boston Partners 7.7M 9.4%
HHLR ADVISORS, LTD. 6.7M 8.2%
Topline Capital Management, LLC 6.3M 7.7%
VANGUARD CAPITAL MANAGEMENT LLC 4.9M 6.1%
GEODE CAPITAL MANAGEMENT, LLC 3.1M 3.8%
DIMENSIONAL FUND ADVISORS LP 2.6M 3.2%
STATE STREET CORP 2.6M 3.1%
GOLDMAN SACHS GROUP INC 2.2M 2.7%
ROYCE & ASSOCIATES LP 2.1M 2.6%
Russell Investments Group, Ltd. 1.5M 1.9%
ACADIAN ASSET MANAGEMENT LLC 1.4M 1.7%
BANK OF AMERICA CORP /DE/ 1.3M 1.6%
VANGUARD PORTFOLIO MANAGEMENT LLC 1.1M 1.4%
CHARLES SCHWAB INVESTMENT MANAGEMENT INC 1.1M 1.3%
NORTHERN TRUST CORP 1.0M 1.2%
HRT FINANCIAL LP 997.8K 1.2%
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP 973.8K 1.2%
JANE STREET GROUP, LLC 906.2K 1.1%
TUDOR INVESTMENT CORP ET AL 837.9K 1.0%
AQR CAPITAL MANAGEMENT LLC 814.0K 1.0%
VANGUARD FIDUCIARY TRUST CO 740.7K 0.9%
CITADEL ADVISORS LLC 721.5K 0.9%
MORGAN STANLEY 701.8K 0.9%

Largest changes

Manager Action Previous Current Change
BlackRock, Inc. Reduced 17.0M 9.6M -7.4M
MILLENNIUM MANAGEMENT LLC Increased 6.3M 9.3M +3.0M
Boston Partners Increased 5.8M 7.7M +1.9M
STATE STREET CORP Reduced 4.1M 2.6M -1.6M
BROWN CAPITAL MANAGEMENT LLC Sold Out 1.5M 0 -1.5M
VANGUARD PORTFOLIO MANAGEMENT LLC Reduced 2.3M 1.1M -1.2M
MORGAN STANLEY Reduced 1.7M 701.8K -1.0M
ACADIAN ASSET MANAGEMENT LLC Increased 399.0K 1.4M +977.1K
JANE STREET GROUP, LLC New 0 906.2K +906.2K
Simcoe Capital LLC Sold Out 882.1K 0 -882.1K
Topline Capital Management, LLC Reduced 7.1M 6.3M -781.0K
Qube Research & Technologies Ltd New 0 689.8K +689.8K
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP Increased 319.9K 973.8K +653.9K
SUSQUEHANNA INTERNATIONAL GROUP, LLP Increased 56.0K 681.7K +625.7K
HRT FINANCIAL LP Increased 414.1K 997.8K +583.7K
CenterBook Partners LP Reduced 729.9K 149.2K -580.7K
PRINCIPAL FINANCIAL GROUP INC Sold Out 534.8K 0 -534.8K
TUDOR INVESTMENT CORP ET AL Increased 320.7K 837.9K +517.2K
MARSHALL WACE, LLP New 0 441.7K +441.7K
ROYCE & ASSOCIATES LP Increased 1.6M 2.1M +439.2K
Point72 Asset Management, L.P. New 0 422.4K +422.4K
Jain Global LLC New 0 411.5K +411.5K
D. E. Shaw & Co., Inc. Increased 260.1K 669.2K +409.1K
Public Sector Pension Investment Board Sold Out 394.7K 0 -394.7K
BANK OF AMERICA CORP /DE/ Increased 1.0M 1.3M +306.3K

13F filings are due 45 days after quarter end and cover long positions in U.S.-listed equities only, so this is a lagged and partial picture: shorts, bonds and foreign listings never appear. Options positions are excluded here rather than folded into the share counts. Political ownership is coming.