Comparable stake leader
Nierenberg Investment Management Company, LLC
SEC ownership of POTBELLY CORP
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001195734.
Disclosed value leader
Nierenberg Investment Management Company, LLC
Comparable rows
4/10
Latest evidence
23 Oct 2025
- Parsed ownership sources
-
3/4/5 and 13D/G
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
Nierenberg Investment Management Company, LLC
Ranking: Comparable ownership first, then disclosed value
- Comparable ownership rows
-
4 of 10
Meaning: Rows with safely comparable ownership %
- Latest 13D/G holder
-
Nierenberg Investment Management Company, LLC
Source: Latest parsed Schedule 13D/G stake
- Latest parsed ownership date
-
23 Oct 2025
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0001195734
- Issuer location
- Chicago, 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 POTBELLY CORP (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
Nierenberg Investment Man...
Disclosed value leader
Nierenberg Investment Man...
Comparable rows
4/10
Latest evidence
23 Oct 2025
3/4/5
13D/G
Lead comparable stake: 10%
6 rows are not safely comparable across share classes.
13D/G row: Nierenberg Investment Management Company, LLC
Showing 1-8 of 10 holder rows.
Quick read
Nierenberg Investment Management Company, LLC leads the comparable SEC ownership view at 10%.
4 of 10 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 Nierenberg Investment Management Company, LLC's linked filing trail.
Comparable ownership
Top 4
Nierenberg Investment Management ...
10%
Portolan Capital Management, LLC
5.5%
GLAZER CAPITAL, LLC
5.3%
RENAISSANCE TECHNOLOGIES LLC
4%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 10 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Nierenberg Investment Management Company, LLC |
3/4/5
13D/G
10%+ Owner · David Nierenberg
|
10%
Reported 13D/G
· 14 Mar 2025
|
$38,818,664
5,555,626 shares
|
— | 07 Aug 2024 |
| Portolan Capital Management, LLC |
13D/G
|
5.5%
Reported 13D/G
· 20 Jun 2025
|
$14,542,361
1,667,702 shares
|
$0 | 20 Jun 2025 |
| GLAZER CAPITAL, LLC |
13D/G
|
5.3%
Reported 13D/G
· 22 Sep 2025
|
$20,096,415
1,605,145 shares
|
$0 | 22 Sep 2025 |
| RENAISSANCE TECHNOLOGIES LLC |
13D/G
|
4%
Reported 13D/G
· 30 Sep 2024
|
$9,722,999
1,201,854 shares
|
$0 | 30 Sep 2024 |
| David Nierenberg |
3/4/5
10%+ Owner
|
—
denominator unverified
|
$29,104,649
3,109,471 shares
|
— | 28 Mar 2025 |
| Marla C. Gottschalk |
3/4/5
Director
|
—
mixed-class rows
|
$1,844,094
167,122 shares
mixed-class rows
|
— | 20 May 2021 |
| Todd Whitney Smith |
3/4/5
Director
|
—
denominator unverified
|
$1,157,569
95,509 shares
|
— | 19 May 2023 |
| Benjamin L. Rosenzweig |
3/4/5
Director
|
—
denominator unverified
|
$1,023,219
84,424 shares
|
— | 20 May 2021 |
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
No eligible buy or sell activity is available for this window. No eligible Buy or Sell transactions are available in this dataset since 15 Nov 2025.
Buys
$0
Insiders: 0
Sells
$0
Insiders: 0
Net
$0
Shares: 0
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 0
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 0 | $0 | $0 | $0 |
| 3-6 | 0 | 0 | $0 | $0 | $0 |
| 6-9 | 0 | 0 | $0 | $0 | $0 |
| 9-12 | 0 | 0 | $0 | $0 | $0 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 23 reporting-owner rows connected to POTBELLY CORP. Open a relationship link for the CIK-to-CIK filing trail.
Rows
23
Largest Forms 3/4/5 holder
Nierenberg Investment Management Company, LLC
Net 12M change
$0
Latest report
23 Oct 2025
Recent insider transactions for POTBELLY CORP
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 |
|---|---|---|---|---|---|---|---|---|---|---|
| No insider transactions were found in the last 12 months for this issuer. | ||||||||||
* marks a reported price that did not pass the local price check.