William M. Thalman - 13 Feb 2026 Form 4/A - Amendment Insider Report for FOSTER L B CO (FSTR)

Role: EVP & CFO
Signature: /s/ William M. Thalman by Judith Balog, attorney-in-fact
Issuer symbol: FSTR
Transactions as of: 13 Feb 2026
Net transactions value: $0
Form type: 4/A - Amendment
Filing time: 09 Mar 2026, 15:48:39 UTC
Date Of Original Report: 18 Feb 2026
Previous filing: 20 Feb 2026
Next filing: 09 Mar 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
THALMAN WILLIAM M	EVP & CFO	L.B. FOSTER COMPANY, 415 HOLIDAY DRIVE, SUITE 100, PITTSBURGH	/s/ William M. Thalman by Judith Balog, attorney-in-fact	09 Mar 2026	0001104808

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	FSTR	Common Stock	Tax liability		-1,007	-1.3%	$31.63^*	73,743	13 Feb 2026	Direct	F1, F2, F3, F4
transaction	FSTR	Common Stock	Tax liability		-1,736	-2.4%	$31.63^*	72,007	14 Feb 2026	Direct	F3, F4, F5

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Shares withheld to pay taxes applicable to the vesting of restricted stock related to the 2024-2026 LTIP awarded on 5/23/24.
F2	An amendment to the original Form 4 was filed on 2/20/2026 to correct the number of shares beneficially owned to reflect the amendment made to the Form 4 originally filed on 2/12/2026. The amendment to the Form 4 was filed on 2/20/2026 to correct the number of shares withheld to pay taxes applicable to 50 percent of the Performance-based stock unit award granted on 3/31/2021 and earned on 2/11/2026.
F3	Includes 18,519 Performance Restricted Stock Units earned under the 2023-2025 Long Term Incentive Plan granted on 2/14/2023; those 18,519 Performance Restricted Stock Units will settle at the end of the performance period on December 31, 2025, upon certification by the Compensation Committee.
F4	Includes 2,385 Performance Restricted Stock Units earned under the 2024-2026 Long Term Incentive Plan granted on 5/23/2024; those 2,385 Performance Restricted Stock Units will settle at the end of the performance period on December 31, 2026, upon certification by the Compensation Committee.
F5	This amendment was filed to correct the number of shares withheld to pay taxes applicable to the vesting of restricted stock related to the 2023-2025 LTIP awarded on 2/14/23.