Comparable stake leader
First Light Asset Management, LLC
SEC ownership of Simulations Plus, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001023459.
Disclosed value leader
Conestoga Capital Advisors, LLC
Comparable rows
50/50
Latest evidence
03 Jun 2026
- Public ticker
- SLP on Nasdaq
- Parsed ownership sources
- 13D/G, 13F, and 3/4/5
- Largest SEC-reported holder
- First Light Asset Management, LLC
- Latest 13D/G holder
- First Light Asset Management, LLC
- Latest parsed ownership date
- 03 Jun 2026
- Issuer CIK
- 0001023459
- Issuer location
- Research Triangle Park, NC
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
2 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of Simulations Plus, 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
First Light Asset Managem...
Disclosed value leader
Conestoga Capital Advisor...
Comparable rows
50/50
Latest evidence
03 Jun 2026
13D/G
13F
3/4/5
Lead comparable stake: 13%
13D/G row: First Light Asset Management, LLC
Showing 1-8 of 50 holder rows.
Quick read
First Light Asset Management, LLC leads the comparable SEC ownership view at 13%.
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 First Light Asset Management, LLC's linked filing trail.
Comparable ownership
Top 5
First Light Asset Management, LLC
13%
Conestoga Capital Advisors, LLC
12%
BlackRock, Inc.
5.8%
Virginia E. Woltosz
16%
Walter S. Woltosz
16%
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 |
|---|---|---|---|---|---|
| First Light Asset Management, LLC |
13D/G
13F
Company
|
13%
|
$48,307,294
2,649,879 shares
|
$0 | 31 Jan 2026 |
| Conestoga Capital Advisors, LLC |
13D/G
Conestoga Capital Advisors
|
12%
|
$85,160,062
2,398,875 shares
|
$0 | 31 Dec 2024 |
| BlackRock, Inc. |
13D/G
13F
Company
|
5.8%
|
$16,802,191
1,170,069 shares
|
$0 | 30 Sep 2025 |
| Virginia E. Woltosz |
3/4/5
10%+ Owner
|
16%
|
$56,696,304
3,252,800 shares
|
-$488,400 | 01 Jun 2026 |
| Walter S. Woltosz |
3/4/5
Director, 10%+ Owner
|
16%
|
$56,696,304
3,252,800 shares
|
-$1,162,823 | 01 Jun 2026 |
| John Anthony DiBella II |
3/4/5
Chief Revenue Officer
|
0.43%
|
$1,437,810
87,140 shares
|
-$44,850 | 03 Jun 2026 |
| Sharlene Evans |
3/4/5
Director
|
0.09%
|
$202,984
17,173 shares
|
— | 01 May 2026 |
| Daniel L. Weiner |
3/4/5
Director
|
0.08%
|
$195,585
16,547 shares
|
— | 01 May 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: -$1,750,682.
Buys
$0
Insiders: 0
Sells
$1,750,682
Insiders: 5
Net
-$1,750,682
Shares: -106,600
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 106,600
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 64,000 | $0 | $1,038,180 | -$1,038,180 |
| 3-6 | 0 | 0 | $0 | $0 | $0 |
| 6-9 | 0 | 20,866 | $0 | $322,444 | -$322,444 |
| 9-12 | 0 | 21,734 | $0 | $390,058 | -$390,058 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-15 of 15 reporting-owner rows connected to Simulations Plus, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
15
Largest Forms 3/4/5 holder
Walter S. Woltosz
Net 12M change
-$1,750,682
Latest report
03 Jun 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Walter S. Woltosz | Director, 10%+ Owner | $56,696,304 | -$1,162,823 | -2% | Filing P/S | 01 Jun 2026 |
| Virginia E. Woltosz | 10%+ Owner | $56,696,304 | -$488,400 | -0.85% | Filing P/S | 01 Jun 2026 |
| John Anthony DiBella II | Chief Revenue Officer | $1,437,810 | -$44,850 | -3% | Filing P/S | 03 Jun 2026 |
| Jill Fiedler-Kelly | President, Services Solutions | $1,286,315 | -$16,530 | -1.3% | Filing P/S | 11 May 2026 |
| David L. Ralph | Director | $559,741 | Mixed | 30 Nov 2021 | ||
| Sharlene Evans | Director | $202,984 | Median | 01 May 2026 | ||
| Daniel L. Weiner | Director | $195,585 | Median | 01 May 2026 | ||
| John Kenneth Paglia | Director | $172,441 | Median | 01 May 2026 | ||
| Lisa LaVange | Director | $168,558 | -$38,079 | -18% | Filing P/S | 01 Dec 2025 |
| William W. Frederick | Evp/Cfo | Mixed | 16 Oct 2025 | |||
| Brett Howell | Business Unit President | Mixed | 19 Oct 2023 | |||
| Steven Chang | President, Immunetrics | Mixed | 19 Oct 2023 | |||
| Shawn Oconnor | Chief Executive Officer | Mixed | 16 Oct 2025 | |||
| Michael E. Raymer | Business Unit President | Mixed | 11 Jun 2024 | |||
| Daniel Szot | Chief Revenue Officer | Mixed | 17 Oct 2024 |
Recent insider transactions for Simulations Plus, 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| John Anthony DiBella II | SLP | Common Stock | Sale | -1.13% | $16,500 | $16.50 | -1,000 | 87,140 | 03 Jun 2026 | Direct |
| Walter S. Woltosz | SLP | Common Stock | Sale | -0.46% | $261,450 | $17.43 | -15,000 | 3,252,800 | 01 Jun 2026 | Direct |
| Walter S. Woltosz | SLP | Common Stock | Sale | -0.46% | $261,450 | $17.43 | -15,000 | 3,252,800 | 01 Jun 2026 | Direct |
| Jill Fiedler-Kelly | SLP | Common Stock | Sale | -1.27% | $16,530 | $16.53 | -1,000 | 77,817 | 11 May 2026 | Direct |
| Jill Fiedler-Kelly | SLP | Common Stock | Options Exercise | 1.29% | 1,000 | 78,817 | 11 May 2026 | Direct | ||
| Jill Fiedler-Kelly | SLP | Employee Stock Option (Right to Buy) | Options Exercise | -10.6% | -1,000 | 8,400 | 11 May 2026 | Direct | ||
| John Anthony DiBella II | SLP | Common Stock | Sale | -1.12% | $14,980 | $14.98 | -1,000 | 88,140 | 04 May 2026 | Direct |
| Walter S. Woltosz | SLP | Common Stock | Sale | -0.46% | $226,950 | $15.13 | -15,000 | 3,267,800 | 04 May 2026 | Direct |
| Walter S. Woltosz | SLP | Common Stock | Sale | -0.46% | $226,950 | $15.13 | -15,000 | 3,267,800 | 04 May 2026 | Direct |
| Sharlene Evans | SLP | Common Stock | Award | 14.1% | 2,117 | 17,173 | 01 May 2026 | Direct | ||
| Walter S. Woltosz | SLP | Common Stock | Award | 0.06% | 2,117 | 3,282,800 | 01 May 2026 | Direct | ||
| Daniel L. Weiner | SLP | Common Stock | Award | 14.7% | 2,117 | 16,547 | 01 May 2026 | Direct | ||
| John Kenneth Paglia | SLP | Common Stock | Award | 17% | 2,117 | 14,589 | 01 May 2026 | Direct | ||
| John Anthony DiBella II | SLP | Common Stock | Sale | -1.11% | $13,370 | $13.37 | -1,000 | 89,140 | 15 Apr 2026 | Direct |
| John Anthony DiBella II | SLP | Common Stock | Options Exercise | 12.9% | 10,300 | 90,140 | 06 Feb 2026 | Direct | ||
| John Anthony DiBella II | SLP | Stock Options (Right to Buy) | Options Exercise | -100% | -10,300 | 0 | 06 Feb 2026 | Direct | ||
| Sharlene Evans | SLP | Common Stock | Award | 13.4% | 1,776 | 15,056 | 30 Jan 2026 | Direct | ||
| John Kenneth Paglia | SLP | Common Stock | Award | 16.6% | 1,776 | 12,472 | 30 Jan 2026 | Direct | ||
| Walter S. Woltosz | SLP | Common Stock | Award | 0.05% | 1,776 | 3,280,683 | 30 Jan 2026 | Direct | ||
| Daniel L. Weiner | SLP | Common Stock | Award | 14% | 1,776 | 14,430 | 30 Jan 2026 | Direct | ||
| Jill Fiedler-Kelly | SLP | Common Stock | Options Exercise | 13% | 8,950 | 77,817 | 28 Jan 2026 | Direct | ||
| Jill Fiedler-Kelly | SLP | Employee Stock Option (Right to Buy) | Options Exercise | -100% | -8,950 | 0 | 28 Jan 2026 | Direct | ||
| Walter S. Woltosz | SLP | Common Stock | Gift | -0.28% | -9,095 | 3,278,907 | 18 Dec 2025 | Direct | ||
| Lisa LaVange | SLP | Common Stock | Sale | -7.99% | $14,644 | $16.91 | -866 | 9,968 | 01 Dec 2025 | Direct |
| Sharlene Evans | SLP | Common Stock | Award | 15.4% | 1,771 | 13,280 | 03 Nov 2025 | Direct | ||
| Lisa LaVange | SLP | Common Stock | Award | 19.5% | 1,771 | 10,834 | 03 Nov 2025 | Direct | ||
| John Kenneth Paglia | SLP | Common Stock | Award | 19.8% | 1,771 | 10,696 | 03 Nov 2025 | Direct | ||
| Walter S. Woltosz | SLP | Common Stock | Award | 0.05% | 1,771 | 3,288,002 | 03 Nov 2025 | Direct | ||
| Daniel L. Weiner | SLP | Common Stock | Award | 16.3% | 1,771 | 12,654 | 03 Nov 2025 | Direct | ||
| Shawn Oconnor | SLP | Stock Options (Right to Buy) | Award | 50,000 | 50,000 | 16 Oct 2025 | Direct | |||
| William W. Frederick | SLP | Stock Options (Right to Buy) | Award | 32,500 | 32,500 | 16 Oct 2025 | Direct | |||
| Jill Fiedler-Kelly | SLP | Stock Options (Right to Buy) | Award | 27,500 | 27,500 | 16 Oct 2025 | Direct | |||
| John Anthony DiBella II | SLP | Stock Options (Right to Buy) | Award | 27,500 | 27,500 | 16 Oct 2025 | Direct | |||
| Walter S. Woltosz | SLP | Common Stock | Sale | -0.6% | $307,800 | $15.39 | -20,000 | 3,286,231 | 01 Oct 2025 | Direct |
| Lisa LaVange | SLP | Common Stock | Sale | -8.73% | $12,225 | $14.10 | -867 | 9,063 | 02 Sep 2025 | Direct |
| Walter S. Woltosz | SLP | Common Stock | Award | 0.06% | 2,074 | 3,306,231 | 01 Aug 2025 | Direct | ||
| Daniel L. Weiner | SLP | Common Stock | Award | 23.5% | 2,074 | 10,883 | 01 Aug 2025 | Direct | ||
| John Kenneth Paglia | SLP | Common Stock | Award | 30.3% | 2,074 | 8,925 | 01 Aug 2025 | Direct | ||
| Sharlene Evans | SLP | Common Stock | Award | 22% | 2,074 | 11,509 | 01 Aug 2025 | Direct | ||
| Lisa LaVange | SLP | Common Stock | Sale | -8.03% | $11,210 | $12.93 | -867 | 9,930 | 01 Aug 2025 | Direct |
| Lisa LaVange | SLP | Common Stock | Award | 23.8% | 2,074 | 10,797 | 01 Aug 2025 | Direct | ||
| Walter S. Woltosz | SLP | Common Stock | Sale | -0.6% | $366,623 | $18.33 | -20,000 | 3,304,157 | 01 Jul 2025 | Direct |
* marks a reported price that did not pass the local price check.