Comparable stake leader
EcoR1 Capital, LLC
SEC ownership of Eton Pharmaceuticals, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001710340.
Disclosed value leader
Opaleye Management Inc.
Comparable rows
50/50
Latest evidence
31 Jul 2026
- Public ticker
- ETON on Nasdaq
- Parsed ownership sources
-
13D/G, 13F, and 3/4/5
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
EcoR1 Capital, LLC
Ranking: Comparable ownership first, then disclosed value
- Comparable ownership rows
-
50 of 50
Meaning: Rows with safely comparable ownership %
- Latest 13D/G holder
-
EcoR1 Capital, LLC
Source: Latest parsed Schedule 13D/G stake
- Latest parsed ownership date
-
31 Jul 2026
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0001710340
- Issuer location
- Deer Park, IL
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
3 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of Eton Pharmaceuticals, Inc. (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
EcoR1 Capital, LLC
Disclosed value leader
Opaleye Management Inc.
Comparable rows
50/50
Latest evidence
31 Jul 2026
13D/G
13F
3/4/5
Lead comparable stake: 7.7%
13D/G row: EcoR1 Capital, LLC
Showing 1-8 of 50 holder rows.
Quick read
EcoR1 Capital, LLC leads the comparable SEC ownership view at 7.7%.
50 of 50 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens EcoR1 Capital, LLC's linked filing trail.
Comparable ownership
Top 5
EcoR1 Capital, LLC
7.7%
BlackRock, Inc.
6.9%
Opaleye Management Inc.
10%
Judith M. Matthews
0.12%
STATE STREET CORP
2.6%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| EcoR1 Capital, LLC |
13D/G
|
7.7%
|
$28,407,583
1,981,003 shares
|
$0 | 31 Dec 2024 |
| BlackRock, Inc. |
13F
13D/G
Company
|
6.9%
from 13D/G
|
$68,629,156
1,895,833 shares
|
— | 30 Jun 2026 |
| Opaleye Management Inc. |
3/4/5
10%+ Owner
|
10%
|
$102,899,116
2,790,000 shares
|
-$5,831,670 | 14 Jul 2026 |
| Judith M. Matthews |
3/4/5
Chief Financial Officer
|
0.12%
|
$142,527
32,246 shares
|
— | 31 Jul 2026 |
| STATE STREET CORP |
13F
Company
|
2.6%
|
$25,404,653
701,786 shares
|
— | 30 Jun 2026 |
| Westside Investment Management, Inc. |
13F
Company
|
1.6%
|
$15,608,010
431,160 shares
|
— | 30 Jun 2026 |
| Nuveen, LLC |
13F
Company
|
1.4%
|
$13,600,593
375,707 shares
|
— | 30 Jun 2026 |
| THOMPSON SIEGEL & WALMSLEY LLC |
13F
Company
|
1.1%
|
$10,760,000
297,232 shares
|
— | 30 Jun 2026 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Net insider flow leans to selling over the last 12 months. Net value: -$15,184,819.
Buys
$0
Insiders: 0
Sells
$15,184,819
Insiders: 5
Net
-$15,184,819
Shares: -466,713
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 466,713
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 425,000 | $0 | $14,511,105 | -$14,511,105 |
| 3-6 | 0 | 0 | $0 | $0 | $0 |
| 6-9 | 0 | 0 | $0 | $0 | $0 |
| 9-12 | 0 | 41,713 | $0 | $673,714 | -$673,714 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-11 of 11 reporting-owner rows connected to Eton Pharmaceuticals, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
11
Largest Forms 3/4/5 holder
Opaleye Management Inc.
Net 12M change
-$15,184,819
Latest report
31 Jul 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Opaleye Management Inc. | 10%+ Owner | $102,899,116 | -$5,831,670 | -5.4% | Filing P/S | 14 Jul 2026 |
| Sean Brynjelsen | President & CEO, Director | $38,988,217 | -$3,825,717 | -8.9% | Mixed | 31 Jul 2026 |
| Norbert G. Riedel | Director | $5,535,723 | Mixed | 31 Jul 2026 | ||
| James R. Gruber | Chief Financial Officer | $3,508,134 | -$673,714 | -16% | Mixed | 12 Jan 2026 |
| David Krempa | Chief Business Officer | $1,546,709 | -$3,229,923 | -68% | Mixed | 31 Jul 2026 |
| Judith M. Matthews | Chief Financial Officer | $142,527 | Mixed | 31 Jul 2026 | ||
| Paul Maier V | Director | $44,200 | Mixed | 31 Jul 2026 | ||
| Charles J. Casamento | Director | $44,200 | Mixed | 31 Jul 2026 | ||
| Ipek Erdogan-Trinkaus | Chief Commercial Officer | $40,610 | Mixed | 31 Jul 2026 | ||
| Jennifer McKie Adams | Director | $0 | -$1,623,795 | -100% | Mixed | 31 Jul 2026 |
| William Wilson Troutman | CFO and Secretary | Mixed | 07 Feb 2022 |
Recent insider transactions for Eton Pharmaceuticals, Inc.
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Charles J. Casamento | ETON | Common Stock | Award | 10,000 | 10,000 | 31 Jul 2026 | Direct | |||
| Judith M. Matthews | ETON | Common Stock | Award | 32,246 | 32,246 | 31 Jul 2026 | Direct | |||
| Ipek Erdogan-Trinkaus | ETON | Common Stock | Award | 80,000 | 80,000 | 31 Jul 2026 | Direct | |||
| Sean Brynjelsen | ETON | Common Stock | Award | 128,985 | 128,985 | 31 Jul 2026 | Direct | |||
| David Krempa | ETON | Common Stock | Award | 128,985 | 128,985 | 31 Jul 2026 | Direct | |||
| Paul Maier V | ETON | Common Stock | Award | 10,000 | 10,000 | 31 Jul 2026 | Direct | |||
| Norbert G. Riedel | ETON | Common Stock | Award | 10,000 | 10,000 | 31 Jul 2026 | Direct | |||
| Jennifer McKie Adams | ETON | Common Stock | Award | 10,000 | 10,000 | 31 Jul 2026 | Direct | |||
| Opaleye Management Inc. | ETON | Common Stock, par value $0.001 per share | Sale | -25% | $499,886 | $37.54 | -13,315 | 40,000 | 14 Jul 2026 | By Managed Account |
| Opaleye Management Inc. | ETON | Common Stock, par value $0.001 per share | Sale | -0.56% | $563,146 | $37.54 | -15,000 | 2,665,000 | 14 Jul 2026 | By Opaleye, L.P. |
| Sean Brynjelsen | ETON | Common Stock | Options Exercise | 23.2% | 200,000 | 1,061,194 | 14 Jul 2026 | Direct | ||
| Sean Brynjelsen | ETON | Employee Stock Option | Options Exercise | 200,000 | 0 | 14 Jul 2026 | Direct | |||
| Sean Brynjelsen | ETON | Common Stock | Options Exercise | 3.3% | 27,500 | 861,194 | 12 Jul 2026 | Direct | ||
| Sean Brynjelsen | ETON | Restricted Stock Units | Options Exercise | -100% | -27,500 | 0 | 12 Jul 2026 | Direct | ||
| David Krempa | ETON | Common Stock | Options Exercise | 37% | 10,000 | 37,025 | 12 Jul 2026 | Direct | ||
| David Krempa | ETON | Restricted Stock Units | Options Exercise | -100% | -10,000 | 0 | 12 Jul 2026 | Direct | ||
| Opaleye Management Inc. | ETON | Common Stock, par value $0.001 per share | Sale | -11.1% | $256,522 | $38.37 | -6,685 | 53,315 | 07 Jul 2026 | By Managed Account |
| Opaleye Management Inc. | ETON | Common Stock, par value $0.001 per share | Sale | -0.74% | $767,456 | $38.37 | -20,000 | 2,680,000 | 07 Jul 2026 | By Opaleye, L.P. |
| Opaleye Management Inc. | ETON | Common Stock, par value $0.001 per share | Sale | -0.37% | $380,000 | $38.00 | -10,000 | 2,700,000 | 06 Jul 2026 | By Opaleye, L.P. |
| Opaleye Management Inc. | ETON | Common Stock, par value $0.001 per share | Sale | -29.4% | $934,628 | $37.39 | -25,000 | 60,000 | 02 Jul 2026 | By Managed Account |
| Opaleye Management Inc. | ETON | Common Stock, par value $0.001 per share | Sale | -2.34% | $2,430,032 | $37.39 | -65,000 | 2,710,000 | 02 Jul 2026 | By Opaleye, L.P. |
| David Krempa | ETON | Restricted Stock Units | Award | 11.5% | 10,000 | 96,829 | 26 Jun 2026 | Direct | ||
| Jennifer McKie Adams | ETON | Common Stock | Sale | -100% | $1,623,795 | $32.48 | -50,000 | 0 | 17 Jun 2026 | Direct |
| Jennifer McKie Adams | ETON | Common Stock | Options Exercise | 50,000 | 50,000 | 17 Jun 2026 | Direct | |||
| Jennifer McKie Adams | ETON | Employee Stock Option | Options Exercise | -100% | -50,000 | 0 | 17 Jun 2026 | Direct | ||
| Sean Brynjelsen | ETON | Common Stock | Sale | -12.6% | $3,825,717 | $31.88 | -120,000 | 833,694 | 28 May 2026 | Direct |
| David Krempa | ETON | Common Stock | Sale | -43.8% | $619,375 | $31.47 | -19,679 | 25,249 | 27 May 2026 | Direct |
| David Krempa | ETON | Common Stock | Options Exercise | 77.9% | 19,679 | 44,928 | 27 May 2026 | Direct | ||
| David Krempa | ETON | Employee Stock Option | Options Exercise | -100% | -19,679 | 0 | 27 May 2026 | Direct | ||
| David Krempa | ETON | Common Stock | Sale | -59.8% | $1,181,732 | $31.49 | -37,524 | 25,249 | 26 May 2026 | Direct |
| David Krempa | ETON | Common Stock | Options Exercise | 148.6% | 37,524 | 62,773 | 26 May 2026 | Direct | ||
| David Krempa | ETON | Employee Stock Option | Options Exercise | -100% | -37,524 | 0 | 26 May 2026 | Direct | ||
| David Krempa | ETON | Common Stock | Sale | -62.9% | $1,428,816 | $33.39 | -42,797 | 25,249 | 22 May 2026 | Direct |
| David Krempa | ETON | Common Stock | Options Exercise | 81.7% | 30,591 | 68,046 | 22 May 2026 | Direct | ||
| David Krempa | ETON | Employee Stock Option | Options Exercise | -19.6% | -30,591 | 125,609 | 22 May 2026 | Direct | ||
| Norbert G. Riedel | ETON | Common Stock | Options Exercise | 91.9% | 32,155 | 67,155 | 21 Apr 2026 | Direct | ||
| Norbert G. Riedel | ETON | Employee Stock Option (Right to Buy) | Options Exercise | -100% | -32,155 | 0 | 21 Apr 2026 | Direct | ||
| Norbert G. Riedel | ETON | Common Stock | Exercise of in-the-money or at-the-money derivative security | 600% | 30,000 | 35,000 | 03 Feb 2026 | Direct | ||
| Norbert G. Riedel | ETON | Employee Stock Option (Right to Buy) | Exercise of in-the-money or at-the-money derivative security | -100% | -30,000 | 0 | 03 Feb 2026 | Direct | ||
| David Krempa | ETON | Common Stock | Tax liability | -0.31% | -1,942 | 630,238 | 14 Jan 2026 | Direct | ||
| James R. Gruber | ETON | Common Stock | Tax liability | -1.06% | -2,293 | 213,420 | 14 Jan 2026 | Direct | ||
| Norbert G. Riedel | ETON | Restricted Stock Units | Award | 2.71% | 7,757 | 294,253 | 12 Jan 2026 | Direct | ||
| Norbert G. Riedel | ETON | Employee Stock Option (Right to Buy) | Award | 4.45% | 12,196 | 286,496 | 12 Jan 2026 | Direct | ||
| Jennifer McKie Adams | ETON | Restricted Stock Units | Award | 4.55% | 7,757 | 178,086 | 12 Jan 2026 | Direct | ||
| Jennifer McKie Adams | ETON | Employee Stock Option (Right to Buy) | Award | 7.71% | 12,196 | 170,329 | 12 Jan 2026 | Direct | ||
| Charles J. Casamento | ETON | Restricted Stock Units | Award | 2.63% | 7,757 | 302,928 | 12 Jan 2026 | Direct | ||
| Charles J. Casamento | ETON | Employee Stock Option (Right to Buy) | Award | 4.31% | 12,196 | 295,171 | 12 Jan 2026 | Direct | ||
| Paul Maier V | ETON | Restricted Stock Units | Award | 2.71% | 7,757 | 294,253 | 12 Jan 2026 | Direct | ||
| Paul Maier V | ETON | Employee Stock Option (Right to Buy) | Award | 4.45% | 12,196 | 286,496 | 12 Jan 2026 | Direct | ||
| Ipek Erdogan-Trinkaus | ETON | Restricted Stock Units | Award | 20.9% | 25,856 | 149,734 | 12 Jan 2026 | Direct |
* marks a reported price that did not pass the local price check.