SCHEDULE Filed 2025-03-17 Event 2025-03-14 SEC 0001013594-25-000381 →

Nierenberg Investment Management Company, Inc. → POTBELLY CORP

Stake: 10.30% Shares: 3,087,302 CUSIP: 73754Y100 Class: Common Stock, par value $0.01

Item 4 — Purpose of Transaction

Item 4 of the Schedule 13D is hereby amended to add the following Language: On March14, 2025, the Reporting Persons submitted a letter to the Board of Directors of the issuer (the "March 14 Letter"). The full text of the March 14 Letter is attached hereto as Exhibit 99.1.

Cross-References

Insider Activity (last 365d)

2 transactions

0 buys · 2 sales · 0 awards/exercises

Issuer Cluster

13 13D/G filings on this issuer

12 other filings besides this one

Filer Track Record

10 filings by this filer

9 other filings in the data moat

Short Interest

—

Not in latest FINRA snapshot

Form 4 Insider Transactions · last 365d

Date	Insider	Role	Type	Shares	Price	Value
2025-10-23	Butler Adrian M	director	Disposition	89,529	$17.12	$1.53M
2025-10-23	Near David	director	Disposition	158,840	$17.12	$2.72M

Other 13D/G Filings on POTBELLY CORP

Filed	Form	Filer	Stake	Shares
2024-03-11	SC	180 DEGREE CAPITAL CORP. /NY/	—	—	view →
2023-12-05	SC	Chain of Lakes Investment Fund, LLC	—	—	view →
2021-02-11	SC	180 DEGREE CAPITAL CORP. /NY/	—	—	view →
2020-08-17	SC	Vann A. AvedisianTrust U/A 8/29/85	—	—	view →
2020-06-29	SC	180 DEGREE CAPITAL CORP. /NY/	—	—	view →
2020-05-11	SC	Vann A. AvedisianTrust U/A 8/29/85	—	—	view →
2020-03-30	SC	Vann A. AvedisianTrust U/A 8/29/85	—	—	view →
2020-03-19	SC	Vann A. AvedisianTrust U/A 8/29/85	—	—	view →
2020-03-02	SC	Vann A. AvedisianTrust U/A 8/29/85	—	—	view →
2019-12-06	SC	Privet Fund LP	—	—	view →
2018-03-21	SC	Privet Fund LP	—	—	view →
2018-02-07	SC	Privet Fund LP	—	—	view →

Other Filings by Nierenberg Investment Management Company, Inc.

Filed	Form	Issuer	Stake	Shares
2025-03-06	SCHEDULE	RIVERVIEW BANCORP INC RVSB	7.70%	1,625,065	view →
2022-02-04	SC	FLOTEK INDUSTRIES INC/CN/ FTK	—	—	view →
2021-11-22	SC	CRAWFORD & CO CRD-B	—	—	view →
2021-03-26	SC	Houston Wire & Cable CO	—	—	view →
2020-09-03	SC	FLOTEK INDUSTRIES INC/CN/ FTK	—	—	view →
2020-08-26	SC	GEOSPACE TECHNOLOGIES CORP GEOS	—	—	view →
2020-03-18	SC	Houston Wire & Cable CO	—	—	view →
2019-12-23	SC	Houston Wire & Cable CO	—	—	view →
2019-02-08	SC	GEOSPACE TECHNOLOGIES CORP GEOS	—	—	view →

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