Assertio Holdings, Inc.
Assertio Holdings, Inc. (ASRT) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · ASRT · as of Sep 30, 2025
Ownership Breakdown
72
Institutional Holders
▼ 4 vs Q2
$22.23M
Total Inst. Value
▲ $6.17M vs Q2
6.46M
Shares Outstanding
freeFloat 96.95%
25.22M
13F Shares Held
▲ 164,047 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
ASRT largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
NANTAHALA CAPITAL MANAGEMENT, LLC pharmaceutical preparations | 8.81M | 9.15% | 9.15% | $7.76B | Nov 14, 2025 | — held |
VANGUARD GROUP INC pharmaceutical preparations | 4.43M | 4.60% | 4.60% | $3.90B | Nov 7, 2025 | ▲ 41.3K |
RENAISSANCE TECHNOLOGIES LLC pharmaceutical preparations | 2.94M | 3.06% | 3.06% | $2.59B | Nov 13, 2025 | ▲ 120.1K |
BLACKROCK, INC. pharmaceutical preparations | 1.36M | 1.42% | 1.42% | $1.20B | Nov 12, 2025 | ▼ 10.0K |
GEODE CAPITAL MANAGEMENT, LLC pharmaceutical preparations | 1.02M | 1.06% | 1.06% | $900.75M | Nov 12, 2025 | ▲ 883 |
CM MANAGEMENT, LLC pharmaceutical preparations | 724.4K | 75.26% | 75.26% | $638.04M | Nov 13, 2025 | — held |
MILLENNIUM MANAGEMENT LLC pharmaceutical preparations | 606.0K | 62.96% | 62.96% | $533.75M | Nov 14, 2025 | ▼ 88.5K |
MORGAN STANLEY pharmaceutical preparations | 597.6K | 62.09% | 62.09% | $526.35M | May 27, 2026 | ▲ 159.1K |
TWO SIGMA ADVISERS, LP pharmaceutical preparations | 427.5K | 44.42% | 44.42% | $376.57M | Nov 14, 2025 | ▼ 5.0K |
GSA CAPITAL PARTNERS LLP pharmaceutical preparations | 381.6K | 39.65% | 39.65% | $336.00M | Nov 7, 2025 | ▲ 321.6K |
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
18
Increased
+825.8K shares3
New Positions
first time holders15
Decreased
−617.1K shares0
Sold Out
fully exitedNet shares change (top 50)
+208.7K
+825.8K / −617.1K
Net new holders
+6
3 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
ASRT insider trading · insider activity
Source: SEC Form 4
6
Buy transactions
1
Sell transactions
6.00
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 |
|---|---|---|---|---|---|---|---|
Mason Heather L director | May 13, 2026 | Gift | 6,666 | — | — | 20.9K | Form 4 ↗ |
Mason Heather L director | May 13, 2026 | Gift | 6,666 | — | — | 6.7K | Form 4 ↗ |
Stark David Matthew director | May 5, 2026 | Award | 4,851 | — | — | 11.4K | Form 4 ↗ |
Emany Sravan Kumar director | May 5, 2026 | Award | 4,851 | — | — | 23.9K | Form 4 ↗ |
Kirk Sigurd director | May 5, 2026 | Award | 4,851 | — | — | 12.0K | Form 4 ↗ |
MCKEE WILLIAM director | May 5, 2026 | Award | 4,851 | — | — | 27.9K | Form 4 ↗ |
Mason Heather L director | May 5, 2026 | Award | 4,851 | — | — | 27.6K | Form 4 ↗ |
Schlessinger Sam EVP, General Counsel | Mar 2, 2026 | Award | 21,128 | $11.77 | $248.7K | 21.1K | Form 4 ↗ |
Schlessinger Sam EVP, General Counsel | Mar 2, 2026 | Award | 18,804 | — | — | 18.8K | Form 4 ↗ |
Patel Ajay EVP and CFO | Mar 2, 2026 | Award | 21,128 | $11.77 | $248.7K | 21.1K | 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
Assertio Holdings, Inc. (ASRT) is primarily owned by institutional investors, who hold approximately 100.0% of total shares outstanding. Company insiders own approximately 3.05%, while retail and public investors account for the remaining 0.00%.
The largest institutional shareholder of Assertio Holdings, Inc. is NANTAHALA CAPITAL MANAGEMENT, LLC, holding approximately 8.81 million shares — equal to 9.15% of outstanding shares — as of September 30, 2025.
A total of 72 institutional investors currently hold ASRT stock, with a combined institutional value of approximately $22,234,086 as of the most recent 13F filing period.
Frequently asked questions
ASRT ownershipAssertio Holdings, Inc. (ASRT) is primarily owned by institutional investors, who hold approximately 100.0% of shares. The largest shareholder is NANTAHALA CAPITAL MANAGEMENT, LLC with a 9.15% stake. Company insiders hold 3.05%. Data sourced from SEC Form 13F as of September 30, 2025.