Cytek Biosciences, Inc.
Cytek Biosciences, Inc. (CTKB) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · CTKB · as of Sep 30, 2025
Ownership Breakdown
153
Institutional Holders
▼ 5 vs Q2
$308.63M
Total Inst. Value
▲ $38.43M vs Q2
129.14M
Shares Outstanding
freeFloat 91.46%
80.03M
13F Shares Held
▲ 566,445 vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
CTKB largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
BLACKROCK, INC. laboratory analytical instruments | 16.55M | 13.04% | 13.04% | $57.42B | Nov 12, 2025 | ▼ 487.8K |
TOPLINE CAPITAL MANAGEMENT, LLC laboratory analytical instruments | 6.94M | 5.47% | 5.47% | $24.10B | Nov 14, 2025 | ▲ 1.71M |
VANGUARD GROUP INC laboratory analytical instruments | 6.93M | 5.46% | 5.46% | $24.06B | Nov 7, 2025 | ▼ 831.6K |
HHLR ADVISORS, LTD. laboratory analytical instruments | 6.66M | 5.24% | 5.24% | $23.10B | Nov 14, 2025 | — held |
BROWN CAPITAL MANAGEMENT LLC laboratory analytical instruments | 4.96M | 3.91% | 3.91% | $17.20B | Nov 4, 2025 | ▼ 2.15M |
STATE STREET CORP laboratory analytical instruments | 4.08M | 3.22% | 3.22% | $14.17B | Nov 14, 2025 | ▼ 89.4K |
MILLENNIUM MANAGEMENT LLC laboratory analytical instruments | 3.42M | 2.69% | 2.69% | $11.86B | Nov 14, 2025 | ▲ 2.49M |
DIMENSIONAL FUND ADVISORS LP laboratory analytical instruments | 3.22M | 2.54% | 2.54% | $11.17B | Nov 12, 2025 | ▼ 237.0K |
GEODE CAPITAL MANAGEMENT, LLC laboratory analytical instruments | 2.78M | 2.19% | 2.19% | $9.66B | Nov 12, 2025 | ▲ 53.9K |
WELLINGTON MANAGEMENT GROUP LLP laboratory analytical instruments | 2.54M | 2.00% | 2.00% | $8.82B | Nov 14, 2025 | NEW |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
22
Increased
+7.19M shares4
New Positions
first time holders22
Decreased
−7.07M shares0
Sold Out
fully exitedNet shares change (top 50)
+118.8K
+7.19M / −7.07M
Net new holders
+4
4 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
CTKB insider trading · insider activity
Source: SEC Form 4
21
Buy transactions
40
Sell transactions
0.53
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Yan Ming CHIEF TECHNOLOGY OFFICER | May 18, 2026 | Tax Withhold | 2,364 | $3.55 | $8.4K | 4.93M | Form 4 ↗ |
Yan Ming CHIEF TECHNOLOGY OFFICER | May 18, 2026 | Tax Withhold | 1,025 | $3.55 | $3.6K | 4.93M | Form 4 ↗ |
Yan Ming CHIEF TECHNOLOGY OFFICER | May 18, 2026 | Tax Withhold | 919 | $3.55 | $3.3K | 4.92M | Form 4 ↗ |
Yan Ming CHIEF TECHNOLOGY OFFICER | May 18, 2026 | Tax Withhold | 1,224 | $3.55 | $4.3K | 4.92M | Form 4 ↗ |
Busque Philippe SVP, GLOBAL SALES AND SERVICES | May 18, 2026 | Tax Withhold | 1,424 | $3.55 | $5.1K | 43.5K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Cytek Biosciences, Inc. (CTKB) is primarily owned by institutional investors, who hold approximately 62.0% of total shares outstanding. Company insiders own approximately 8.54%, while retail and public investors account for the remaining 29.49%.
The largest institutional shareholder of Cytek Biosciences, Inc. is BLACKROCK, INC., holding approximately 16.55 million shares — equal to 13.04% of outstanding shares — as of September 30, 2025.
A total of 153 institutional investors currently hold CTKB stock, with a combined institutional value of approximately $308,628,168 as of the most recent 13F filing period.
Frequently asked questions
CTKB ownershipCytek Biosciences, Inc. (CTKB) is primarily owned by institutional investors, who hold approximately 62.0% of shares. The largest shareholder is BLACKROCK, INC. with a 13.04% stake. Company insiders hold 8.54%. Data sourced from SEC Form 13F as of September 30, 2025.