Vaxart, Inc.
Vaxart, Inc. (VXRT) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · VXRT · as of Sep 30, 2025
Ownership Breakdown
17
Institutional Holders
▼ 83 vs Q2
$839,886
Total Inst. Value
▼ $9.47M vs Q2
242.04M
Shares Outstanding
freeFloat 98.48%
2.34M
13F Shares Held
▼ 20.48M 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
VXRT largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
MARSHALL WACE, LLP biological products, (no diagnostic substances) | 1.95M | 85.52% | 85.52% | $703.09M | Nov 13, 2025 | ▲ 189.2K |
XTX TOPCO LTD biological products, (no diagnostic substances) | 94.3K | 4.13% | 4.13% | $34.40M | Nov 14, 2025 | ▲ 70.4K |
HBK SORCE ADVISORY LLC biological products, (no diagnostic substances) | 75.1K | 3.29% | 3.29% | $26.22M | Oct 16, 2025 | — held |
BEACON CAPITAL MANAGEMENT, LLC biological products, (no diagnostic substances) | 60.3K | 2.64% | 2.64% | $22.01M | Nov 7, 2025 | — held |
CUSTOS FAMILY OFFICE, LLC biological products, (no diagnostic substances) | 50.0K | 2.19% | 2.19% | $18.24M | Oct 16, 2025 | ▲ 40.0K |
LVM CAPITAL MANAGEMENT LTD/MI biological products, (no diagnostic substances) | 25.0K | 1.09% | 1.09% | $9.00M | Oct 9, 2025 | — held |
HERITAGE WEALTH ADVISORS biological products, (no diagnostic substances) | 22.0K | 0.96% | 0.96% | $8.02M | Nov 13, 2025 | ▲ 500 |
SIMPLEX TRADING, LLC biological products, (no diagnostic substances) | 18.6K | 0.81% | 0.81% | $6.00M | Nov 12, 2025 | ▲ 5.7K |
ADVISOR GROUP HOLDINGS, INC. biological products, (no diagnostic substances) | 14.2K | 0.62% | 0.62% | $5.30M | Nov 14, 2025 | ▼ 1.3K |
BAADER BANK AKTIENGESELLSCHAFT biological products, (no diagnostic substances) | 12.1K | 0.53% | 0.53% | $2.73M | Nov 6, 2025 | ▲ 12.1K |
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
6
Increased
+317.8K shares2
New Positions
first time holders1
Decreased
−1.3K shares33
Sold Out
fully exitedNet shares change (top 50)
+316.6K
+317.8K / −1.3K
Net new holders
-26
2 new / 33 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
VXRT insider trading · insider activity
Source: SEC Form 4
Insiders have been net buyers of shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
1
Buy transactions
0
Sell transactions
0.00
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 |
|---|---|---|---|---|---|---|---|
Watson W. Mark director | May 22, 2026 | Purchase | 10,000 | $0.65 | $6.5K | 134.1K | Form 4 ↗ |
Grasman Jeroen Nicolaas Chief Financial Officer | May 19, 2026 | Tax Withhold | 31,395 | $0.61 | $19.2K | 545.6K | Form 4 ↗ |
BREITMEYER JAMES B director | Apr 23, 2026 | Award | 157,400 | $0.74 | $116.5K | 157.4K | Form 4 ↗ |
BREITMEYER JAMES B director | Apr 23, 2026 | Award | 78,800 | — | — | 78.8K | Form 4 ↗ |
Tucker Sean SVP, Chief Scientific Officer | Mar 28, 2026 | Tax Withhold | 3,924 | $0.65 | $2.6K | 882.8K | Form 4 ↗ |
Cummings James F. Chief Medical Officer | Mar 28, 2026 | Tax Withhold | 3,292 | $0.65 | $2.1K | 924.2K | Form 4 ↗ |
Berg Edward B SVP, General Counsel | Mar 24, 2026 | Tax Withhold | 36,418 | $0.69 | $25.3K | 755.4K | Form 4 ↗ |
Cummings James F. Chief Medical Officer | Mar 24, 2026 | Tax Withhold | 30,551 | $0.69 | $21.2K | 927.5K | Form 4 ↗ |
Lo Steven President, Chief Exec Officer | Mar 24, 2026 | Tax Withhold | 126,028 | $0.69 | $87.5K | 2.49M | Form 4 ↗ |
Tucker Sean SVP, Chief Scientific Officer | Mar 24, 2026 | Tax Withhold | 36,418 | $0.69 | $25.3K | 886.7K | 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
Vaxart, Inc. (VXRT) is primarily owned by institutional investors, who hold approximately 1.0% of total shares outstanding. Company insiders own approximately 1.52%, while retail and public investors account for the remaining 97.51%.
The largest institutional shareholder of Vaxart, Inc. is MARSHALL WACE, LLP, holding approximately 1.95 million shares — equal to 85.52% of outstanding shares — as of September 30, 2025.
A total of 17 institutional investors currently hold VXRT stock, with a combined institutional value of approximately $839,886 as of the most recent 13F filing period.
Frequently asked questions
VXRT ownershipVaxart, Inc. (VXRT) is primarily owned by institutional investors, who hold approximately 1.0% of shares. The largest shareholder is MARSHALL WACE, LLP with a 85.52% stake. Company insiders hold 1.52%. Data sourced from SEC Form 13F as of September 30, 2025.