# EDGAR Filing Document

**Accession Number:** 0000277509
**File Stem:** 0000277509-25-000040
**Filing Date:** 2025-6
**Character Count:** 40748
**Document Hash:** 33b1bb766b5ae1811bd97e11b6dded81
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000277509-25-000040.hdr.sgml**: 20250627

**ACCESSION NUMBER**: 0000277509-25-000040

**CONFORMED SUBMISSION TYPE**: 11-K

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20241231

**FILED AS OF DATE**: 20250627

**DATE AS OF CHANGE**: 20250627

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** FEDERAL SIGNAL CORP /DE/
- **CENTRAL INDEX KEY:** 0000277509
- **STANDARD INDUSTRIAL CLASSIFICATION:** MOTOR VEHICLES & PASSENGER CAR BODIES [3711]
- **ORGANIZATION NAME:** 04 Manufacturing
- **EIN:** 361063330
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 11-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-06003
- **FILM NUMBER:** 251087296

**BUSINESS ADDRESS:**
- **STREET 1:** 1333 BUTTERFIELD ROAD
- **STREET 2:** SUITE 500
- **CITY:** DOWNERS GROVE
- **STATE:** IL
- **ZIP:** 60515
- **BUSINESS PHONE:** 630-954-2000

**MAIL ADDRESS:**
- **STREET 1:** 1333 BUTTERFIELD ROAD
- **STREET 2:** SUITE 500
- **CITY:** DOWNERS GROVE
- **STATE:** IL
- **ZIP:** 60515

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** FEDERAL SIGN & SIGNAL CORP /DE/
- **DATE OF NAME CHANGE:** 19600201

<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**___________________________________** 

**FORM 11-K**

**___________________________________** 

**(Mark One)**

⌧ **ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934**

**For the fiscal year ended December 31, 2024** 

**OR**

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| | |
|:---|:---|
| ◻ | **TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934** |

---

**For the transition period from <u>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</u> to <u>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</u>**

**Commission file number: 1-6003**

**___________________________________**

A. Full title of the plan and the address of the plan, if different from that of the issuer named below:

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

B. Name of issuer of the securities held pursuant to the plan and the address of its principal executive office:

**FEDERAL SIGNAL CORPORATION**

**1333 Butterfield Road, Suite 500**

**Downers Grove, Illinois 60515**

&nbsp;&nbsp;&nbsp;&nbsp;

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**TABLE OF CONTENTS**

---

| | |
|:---|:---|
| | **Page** |
| <u>[Report of Independent Registered Public Accounting Firm](#i603a80ccaaa6462fbfbcc447edb282e8_10)</u> | <u>[1](#i603a80ccaaa6462fbfbcc447edb282e8_10)</u> |
| <u>[Required Information](#i603a80ccaaa6462fbfbcc447edb282e8_13)</u> | <u>[2](#i603a80ccaaa6462fbfbcc447edb282e8_13)</u> |
| Financial Statements: |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<u>[Statements of Net Assets Available for Benefits as of December 31, 202](#i603a80ccaaa6462fbfbcc447edb282e8_16)[4](#i603a80ccaaa6462fbfbcc447edb282e8_16)[and 202](#i603a80ccaaa6462fbfbcc447edb282e8_16)[3](#i603a80ccaaa6462fbfbcc447edb282e8_16)</u> | <u>[3](#i603a80ccaaa6462fbfbcc447edb282e8_16)</u> |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<u>[Statement of Changes in Net Assets Available for Benefits for the Year Ended December 31, 202](#i603a80ccaaa6462fbfbcc447edb282e8_19)[4](#i603a80ccaaa6462fbfbcc447edb282e8_19)</u> | <u>[4](#i603a80ccaaa6462fbfbcc447edb282e8_19)</u> |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<u>[Notes to Financial Statements](#i603a80ccaaa6462fbfbcc447edb282e8_22)</u> | <u>[5](#i603a80ccaaa6462fbfbcc447edb282e8_22)</u> |
| Supplemental Information: |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<u>[Schedule H, Line 4](#i603a80ccaaa6462fbfbcc447edb282e8_1649267442226)[a](#i603a80ccaaa6462fbfbcc447edb282e8_1649267442226)[– Schedule of](#i603a80ccaaa6462fbfbcc447edb282e8_1649267442226)[Del](#i603a80ccaaa6462fbfbcc447edb282e8_1649267442226)[inquent Participant Contributions for the Year](#i603a80ccaaa6462fbfbcc447edb282e8_1649267442226)[Ended](#i603a80ccaaa6462fbfbcc447edb282e8_1649267442226)[December 31, 2024](#i603a80ccaaa6462fbfbcc447edb282e8_1649267442226)</u> | <u>[11](#i603a80ccaaa6462fbfbcc447edb282e8_1649267442226)</u> |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<u>[Schedule H, Line 4i – Schedule of Assets (Held at End of Year) as of December 31, 202](#i603a80ccaaa6462fbfbcc447edb282e8_52)[4](#i603a80ccaaa6462fbfbcc447edb282e8_52)</u> | <u>[12](#i603a80ccaaa6462fbfbcc447edb282e8_52)</u> |
| <u>[EXHIBIT INDEX](#i603a80ccaaa6462fbfbcc447edb282e8_55)</u> | <u>[13](#i603a80ccaaa6462fbfbcc447edb282e8_55)</u> |
| <u>[SIGNATURES](#i603a80ccaaa6462fbfbcc447edb282e8_58)</u> | <u>[14](#i603a80ccaaa6462fbfbcc447edb282e8_58)</u> |

---

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**FEDERAL SIGNAL CORPORATION** 

**RETIREMENT SAVINGS PLAN** 

**FINANCIAL STATEMENTS AND** 

**SUPPLEMENTAL INFORMATION** 

December 31, 2024 and 2023

and the

Year Ended December 31, 2024

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM** 

**Federal Signal Benefits Administration Committee and Benefits Planning Committee and Plan Participants**

**Federal Signal Corporation Retirement Savings Plan**

**Downers Grove, Illinois**

**Opinion on the Financial Statements**

We have audited the accompanying statements of net assets available for benefits of the Federal Signal Corporation Retirement Savings Plan (the "Plan") as of December 31, 2024 and 2023, the related statement of changes in net assets available for benefits for the year ended December 31, 2024, and the related notes and schedules (collectively referred to as the financial statements).

In our opinion, the financial statements referred to above present fairly, in all material respects, the net assets available for benefits of the Plan as of December 31, 2024 and 2023, and the changes in net assets available for benefits for the year ended December 31, 2024, in conformity with accounting principles generally accepted in the United States of America.

**Basis for Opinion**

These financial statements are the responsibility of the Plan's management. Our responsibility is to express an opinion on the Plan's financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) ("PCAOB") and are required to be independent with respect to the Plan in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

**Supplemental Information**

The accompanying supplemental schedules of assets (held at end of year) and delinquent participant contributions as of and for the year ended December 31, 2024, have been subjected to audit procedures performed in conjunction with our audit of the 2024 Federal Signal Corporation Retirement Savings Plan financial statements. The supplemental information is the responsibility of the Plan's management. Our audit procedures included determining whether the supplemental information reconciles to the financial statements or the underlying accounting and other records, as applicable, and performing procedures to test the completeness and accuracy of the information presented in the supplemental schedules. In forming our opinion on the supplemental information, we evaluated whether the supplemental information, including its form and content, is presented in conformity with the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. In our opinion, the supplemental information is fairly stated, in all material respects, in relation to the financial statements as a whole.

/s/ REHMANN ROBSON LLC

We have served as Federal Signal Corporation Retirement Savings Plan's independent auditor since 2023.

Grand Rapids, Michigan

June 27, 2025

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**REQUIRED INFORMATION**

Federal Signal Corporation is the Plan Sponsor of the Federal Signal Corporation Retirement Savings Plan (the "Plan"). The Plan is subject to the Employee Retirement Income Security Act of 1974 ("ERISA"). Therefore, in lieu of the requirements of Items 1-3 of Form 11-K, the financial statements of the Plan as of December 31, 2024 and 2023, and for the year ended December 31, 2024, and the supplemental information as of and for the year ended December 31, 2024, have been prepared in accordance with the financial reporting requirements of ERISA.

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**STATEMENTS OF NET ASSETS AVAILABLE FOR BENEFITS**

---

| | | |
|:---|:---|:---|
| | **As of December 31,** | **As of December 31,** |
| | **2024** | **2023** |
| **<u>ASSETS</u>** |  |  |
| Investments, at fair value | $534497275 | $484662559 |
| Receivables: |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Employer contributions | 2481592 | 2277979 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Notes receivable from participants | 7122012 | 6712433 |
| NET ASSETS AVAILABLE FOR BENEFITS | $544100879 | $493652971 |

---

See Notes to Financial Statements

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**STATEMENT OF CHANGES IN NET ASSETS AVAILABLE FOR BENEFITS**

---

| | |
|:---|:---|
| | **Year Ended December 31, 2024** |
| **<u>ADDITIONS</u>** | |
| Investment income: |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Net appreciation in fair value of investments | $51558610 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Interest and dividend income | 11211085 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total investment income | 62769695 |
| Interest income on notes receivable from participants | 508027 |
| Contributions: |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Employer | 12747663 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Participants | 20246272 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Rollovers | 1255072 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total contributions | 34249007 |
| TOTAL ADDITIONS | 97526729 |
| **<u>DEDUCTIONS</u>** |  |
| Benefits paid to participants | (46646028) |
| Administrative expenses | (432793) |
| TOTAL DEDUCTIONS | (47078821) |
| NET INCREASE IN NET ASSETS AVAILABLE FOR BENEFITS | 50447908 |
| NET ASSETS AVAILABLE FOR BENEFITS: |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Beginning of year | 493652971 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;End of year | $544100879 |

---

See Notes to Financial Statements

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**NOTES TO FINANCIAL STATEMENTS**

**NOTE 1 – DESCRIPTION OF PLAN**

The following description of the Federal Signal Corporation Retirement Savings Plan (the "Plan") provides only general information. Participants should refer to the Plan document or Summary Plan Description for a more complete description of the Plan's provisions, which are available from the Plan administrator.

*General*

The Plan is a defined contribution plan covering the majority of the U.S. employees of Federal Signal Corporation (the "Company"). All eligible employees may commence participation in the Plan on their date of hire unless their participation in the Plan is governed by a collective bargaining agreement, in which case they are eligible to participate in the Plan on the first day following completion of their waiting period. The Plan is subject to the provisions of the Employee Retirement Income Security Act of 1974 ("ERISA"). The Plan was amended and restated as of January 1, 2020.

The Plan is sponsored by the Company and administered by the Company's Benefits Administration Committee (the "Committee"), which is comprised of Company-designated management. The Committee has overall responsibility for the operation and administration of the Plan and reports to the Company's Benefits Planning Committee and the Compensation and Benefits Committee of the Company's Board of Directors.

*Contributions*

Most participants can contribute up to 40% of pre-tax annual compensation, as defined in the Plan, and can make Roth contributions. A participant's aggregate pre-tax contributions and Roth contributions for any pay period may not exceed 40% of the participant's compensation for that pay period.

In most circumstances, if an employee does not affirmatively enroll or decline enrollment in the Plan within 30 days of first becoming eligible to participate in the Plan, the employee will be automatically enrolled in the Plan with contributions set at 2% of pre-tax annual compensation to the Vanguard Target Retirement Fund whose "target" year is closest to the year in which the employee will turn age 65. The Plan offers an automatic increase feature that will increase the pre-tax contribution rate of participants by one percentage point each January up to 10% of base pay not to exceed the Internal Revenue Service (the "IRS") contribution limit. The automatic enrollment and automatic increase features also apply to employees covered by certain collective bargaining agreements. Participants may also transfer amounts representing distributions from other qualified defined benefit or defined contribution plans. Additionally, participants age 50 or older, who are making contributions to the Plan, are allowed to make catch-up contributions as defined in the Plan. Contributions are subject to certain Internal Revenue Code of 1986, as amended (the "IRC"), limitations.

For most participants, Company contributions are based on a percentage of participant contributions. The Company makes a safe-harbor matching contribution equal to 100% of the first 3% and 50% of the next 2% of base compensation that a participant contributes to the Plan each pay period.

Many participants also receive a Company-paid annual service-based contribution, ranging from 0.5% to 3.0%, based on years of service.

The Plan provides for an employee stock ownership feature wherein participants have the option of receiving Company stock dividends in cash instead of having the dividends automatically reinvested in the Plan.

*Participant Accounts*

Each participant's account is credited with the participant's contribution and allocations of (a) the Company's contributions and (b) the Plan's earnings in the fund(s) selected by the participant. Each participant's account is also charged with an allocation of investment management fees, administrative expenses, and/or losses. Allocations are based on participant earnings or account balances, as defined. The benefit to which a participant is entitled is the benefit that can be provided from the participant's vested account.

*Vesting* 

Participants are immediately vested in their contributions plus actual earnings thereon. Effective January 1, 2018, most participants are also immediately vested in Company contributions. Participants are immediately vested in the dividends from Company stock that were paid to the Plan and reinvested in Company stock at the participant's election.

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**NOTES TO FINANCIAL STATEMENTS — (CONTINUED)**

*Participant Investment Account Options*

Participants direct the investment of all contributions into various investment options offered by the Plan. Upon enrollment in the Plan, a participant may direct employee contributions in 1% increments in a variety of investment choices at Vanguard Fiduciary Trust Company ("Vanguard") or into the Federal Signal Stock Fund (the "Fund"). Participants may change their investment by contacting Vanguard.

Each participant who has an interest in the Fund is entitled to exercise voting rights attributable to the shares allocated to the participant's Fund account and is notified by the Trustee, Vanguard, as defined by the Plan, prior to the time that such rights are to be exercised. If the Trustee does not receive timely instructions, the Trustee itself or by proxy shall vote all such shares in the same ratio as the shares with respect to which instructions were received from participants.

*Notes Receivable from Participants* 

Participants generally may borrow from their vested contributions a minimum of $1,000 up to a maximum equal to the lesser of $50,000 or 50% of their vested account balance. Loan transactions are treated as a transfer to (from) the investment fund from (to) the participant loan fund. Loans are required to be repaid within five years, with the exception that a loan which is used to acquire a principal residence may be repaid within ten years. The loans are secured by the balance in the participant's account and bear interest at a rate of prime plus one percent. The interest rates are fixed at the date the loans are issued and ranged from 4.25% to 9.50% as of December 31, 2024. Principal and interest are paid ratably through payroll deductions. Upon distribution of a participant's balance before a loan is repaid in full, the unpaid loan balance, together with the loan interest, shall become due and payable, and the trustee will first satisfy the indebtedness of the participant's account before making any distribution to the participant. If a participant ceases to make loan repayments and the Plan administrator deems the participant loan to be in default, foreclosure on the note and attachment of security on such loan will not occur until a distributable event occurs under the Plan.

The loan origination fee for non-automated loans is $85. The loan origination fee for automated loans is $35.

*Payment of Benefits*

Participants are eligible to receive the vested portion of their plan account upon retirement, termination of employment, financial hardship, or total and permanent disability. Payment will generally be made in a lump sum.

*Forfeited Accounts*

Forfeited non-vested accounts totaled $10,692 as of December 31, 2024 and $16,392 as of December 31, 2023. These accounts are used to reduce employer contributions and/or to pay plan expenses. During the year ended December 31, 2024, plan administrative expenses of $46,389 were paid using forfeited non-vested accounts.

**NOTE 2 – SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES**

*Basis of Accounting*

The financial statements of the Plan are prepared under the accrual method of accounting.

*Use of Estimates*

The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("GAAP") requires management to make estimates and assumptions that affect reported amounts of assets and liabilities, and changes therein, and disclosures of contingent assets and liabilities. Accordingly, actual results may differ from those estimates.

*Investment Valuation and Income Recognition*

The Plan's investments are reported at fair value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The Plan's Investment Committee determines the Plan's valuation policies utilizing information provided by the asset custodian. See Note 3 – Fair Value Measurement for further discussion.

The Plan allows participants to invest in the common stock of the Company through the Fund. The Fund consists of the Company's common stock and a balance in the Northern Trust Short-Term Investment Fund, sufficient to meet the Fund's daily

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**NOTES TO FINANCIAL STATEMENTS — (CONTINUED)**

cash needs. Unitizing the Fund allows for daily trades. The Fund is valued at its year-end unit closing price (composed of the year-end market price plus the un-invested cash portion). As of December 31, 2024, the Plan held 620,024 shares of the Company's common stock at a value of $57,284,017. As of December 31, 2023, the Plan held 638,751 shares of the Company's common stock at a value of $49,017,752.

Purchases and sales of securities are recorded on a trade-date basis. In the event there is an extraordinary event related to the Fund resulting in a material trading impact, the transaction will be re-priced. A material trading impact is defined as activity that causes more than negative 10 basis points of price differential. Trading impact becomes material when (a) net participant activity exceeds 2% of the Fund's holdings of Company stock, (b) trade execution prices are significantly different from the closing price used to value the participant's trade date unit value, or (c) a combination of both occurs.

Dividend income is recorded on the ex-dividend date. Interest income is recognized, when earned, on an accrual basis. Net appreciation in fair value of investments includes gains and losses on the investments bought and sold as well as held during the year.

*Notes Receivable from Participants*

Notes receivable from participants are measured at their unpaid principal balance plus accrued but unpaid interest. Interest income is recorded on an accrual basis. If a participant ceases to make loan repayments and the Plan administrator deems the participant loan to be in default, the participant loan balance is reduced and a benefit payment is recorded upon occurrence of a distributable event.

*Contributions*

Participant contributions are recorded when withheld from compensation. Employer contributions are recorded in the period in which they become obligations of the Company.

*Unit Values*

Individual participant accounts for the common/collective trust funds are maintained on a unit value basis. Participants do not have beneficial ownership in the specific underlying securities or other assets in the fund but do have an interest therein represented by units valued daily. The funds earn dividends and interest which are automatically reinvested in additional units. Generally, contributions to and withdrawals from the funds are converted to units by dividing the amounts of such transactions by the unit values as last determined, and the participants' accounts are charged or credited with the number of units properly attributable to each participant.

*Payment of Benefits*

Benefits are recorded when paid.

*Administrative Expenses*

Certain expenses of the Plan are paid by the Company and are not included in the statement of changes in net assets available for benefits. Certain fees paid by the Plan to Vanguard (as trustee) are not included in the administrative expenses and relate to the administration of (a) notes receivable from participants, which are deducted from the proceeds of a participant's loan, and (b) benefit payments, which are charged directly to the participant's account. Investment-related expenses that are structured as a revenue-sharing arrangement are paid directly from fund earnings and are included in net appreciation in fair value of investments.

**NOTE 3 – FAIR VALUE MEASUREMENTS**

Accounting Standards Codification 820, *Fair Value Measurement*, provides the framework for measuring fair value. That framework provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• Level 1 – Inputs to the valuation methodology are unadjusted quoted prices for identical assets or liabilities in active markets that the Plan has the ability to access.

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**NOTES TO FINANCIAL STATEMENTS — (CONTINUED)**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• Level 2 – Inputs to the valuation methodology include quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in inactive markets; inputs other than quoted market prices that are observable for the asset or liability; and inputs that are derived principally from or corroborated by observable market data by correlation or other means. If the asset or liability has a specified (contractual) term, the Level 2 input must be observable for substantially the full term of the asset or liability.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• Level 3 – Inputs to the valuation methodology are unobservable and significant to the fair value measurement.

The asset's or liability's fair value measurement level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Valuation techniques used need to maximize the use of observable inputs and minimize the use of unobservable inputs. Following is a description of the valuation methodologies used for assets measured at fair value. There have been no changes in the methodologies used as of December 31, 2024 and 2023.

*Mutual funds*

Mutual funds are valued at the daily closing price as reported by a nationally-recognized security exchange. Mutual funds held by the Plan are open-end mutual funds that are registered with the Securities and Exchange Commission. These funds are required to publish their daily Net Asset Value ("NAV") and to transact at that price. The mutual funds held by the Plan are deemed to be actively traded.

*Federal Signal Corporation common stock fund*

The Federal Signal Corporation common stock fund is valued at the closing price reported on the active market on which the security is traded plus a small balance held in the Northern Trust Short-Term Investment Fund.

*Common/collective trusts*

Valued based on the year-end unit NAV. The NAV, as provided by the trustee, Vanguard, is used as a practical expedient to estimating fair value. Participant transactions (purchases and sales) may occur daily. Were the Plan to initiate a full redemption of the collective trust, the investment advisor reserves the right to temporarily delay withdrawal from the trust to ensure that securities liquidations will be carried out in an orderly business manner.

The preceding methods described may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. Furthermore, although the Plan's management believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different fair value measurement at the reporting date.

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<u>[**Table of Contents**](#i603a80ccaaa6462fbfbcc447edb282e8_4)</u>

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**NOTES TO FINANCIAL STATEMENTS — (CONTINUED)**

The following table sets forth by level, within the fair value hierarchy, the Plan's investments at fair value as of December 31, 2024:

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| | | | | |
|:---|:---|:---|:---|:---|
| | **Level 1** | **Level 2** | **Level 3** | **Total** |
| Mutual funds | $202232517 | $— | $— | $202232517 |
| Common stock fund | 57362704 |  |  | 57362704 |
| Total investments categorized within fair value hierarchy | $259595221 | $— | $— | $259595221 |
| Investments measured at net asset value: |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Common/collective trusts\* |  |  |  | 274902054 |
| Total investments at fair value |  |  |  | $534497275 |

---

The following table sets forth by level, within the fair value hierarchy, the Plan's investments at fair value as of December 31, 2023:

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| | | | | |
|:---|:---|:---|:---|:---|
| | **Level 1** | **Level 2** | **Level 3** | **Total** |
| Mutual funds | $181663868 | $— | $— | $181663868 |
| Common stock fund | 49658092 |  |  | 49658092 |
| Total investments categorized within fair value hierarchy | $231321960 | $— | $— | $231321960 |
| Investments measured at net asset value: |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Common/collective trusts\* |  |  |  | 253340599 |
| Total investments at fair value |  |  |  | $484662559 |

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\*&nbsp;&nbsp;&nbsp;&nbsp;These funds are measured at fair value using the net asset value per share (or its equivalent) practical expedient and have not been categorized in the fair value hierarchy. The fair value amount presented in this table is intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statements of net assets available for benefits. The common/collective trusts provide for daily redemption by the Plan at reported NAV, provided notice is received at Vanguard before 4:00 pm Eastern time on days the market is open. Additionally, there are no unfunded commitments.

**NOTE 4 – RELATED PARTY AND PARTY-IN-INTEREST TRANSACTIONS**

Certain Plan investments are shares of mutual funds or a common/collective trust fund managed by Vanguard. Vanguard is the trustee as defined by the Plan, and therefore, these transactions qualify as party-in-interest transactions. Fees incurred by the Plan for investment management services are included in net appreciation in fair value of investments, as they are paid through revenue sharing, rather than a direct payment. The Plan made direct payments to the trustee of $443,439 for the year ended December 31, 2024, which were not covered by revenue sharing. The payments to the trustee included $16,185 of loan origination fees paid by participants that are not included in administrative expenses. The Plan also paid certain expenses related to the Plan's operations to various service providers. These transactions are party-in-interest transactions under ERISA. Participants or the Plan Sponsor directly pay any other fees related to the Plan's operations.

Certain Plan investments are shares of the Fund. The Company is the Plan Sponsor; therefore these transactions are considered party-in-interest transactions. Certain receivables are loans to participant employees of the Company, and therefore these transactions are considered party-in-interest transactions. During the year ended December 31, 2024, the Plan recorded income from dividends paid on Company stock of $307,276.

These party-in-interest transactions are exempt from the prohibited transactions rules under ERISA.

**NOTE 5 – TAX STATUS**

The IRS has determined and informed the Company, by a letter dated April 12, 2017, that the Plan (as restated January 1, 2015) and related trust are designed in accordance with applicable requirements of the IRC. Although the Plan has been amended and restated since receiving the determination letter, the Plan administrator believes that the Plan and related trust are currently designed and being operated in compliance with the applicable requirements of the IRC.

U.S. GAAP requires Plan management to evaluate tax positions taken by the Plan and recognize a tax liability (or asset) if the Plan has taken an uncertain tax position that more likely than not would not be sustained upon examination by the IRS. Plan

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**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**NOTES TO FINANCIAL STATEMENTS — (CONTINUED)**

management has analyzed the tax positions taken by the Plan and has concluded that as of December 31, 2024 and December 31, 2023, there are no uncertain tax positions taken or expected to be taken that would require recognition of a liability (or asset) or disclosure in the financial statements. While the Plan may be subject to routine audits by taxing jurisdictions, there are currently no audits for any tax periods in progress.

**NOTE 6 – PLAN TERMINATION**

Although it has not expressed any intent to do so, the Company has the right under the Plan to discontinue its contributions at any time and to terminate the Plan subject to the provisions of ERISA. In the event of Plan termination, participants would become 100% vested in their accounts.

**NOTE 7 – RISKS AND UNCERTAINTIES**

The Plan invests in various investment securities, which are exposed to various risks such as interest rate, credit, and market risks. Due to the level of risk associated with certain investment securities, it is at least reasonably possible that changes in the values of investment securities will occur in the near term and that such changes could materially affect participants' account balances and the amounts reported in the statements of net assets available for benefits.

**NOTE 8 – DELINQUENT PARTICIPANT CONTRIBUTIONS AND LOAN REPAYMENTS**

During the year ended December 31, 2024, the Company did not remit certain participant contributions and loan repayments to the Plan on a timely basis as defined by the Department of Labor's Rules and Regulations for Reporting and Delinquent Participant Contributions Disclosure under ERISA. Untimely remittances on the Schedule H, Line 4(a) - Schedule of Delinquent Participant Contributions, which totaled $17,611 in 2024, were corrected during 2024. Lost earnings were remitted in 2025.

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**SUPPLEMENTAL INFORMATION**

**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**SCHEDULE H, LINE 4a – SCHEDULE OF DELINQUENT PARTICIPANT CONTRIBUTIONS** 

For the Year Ended December 31, 2024

**EIN: 36-1063330**

**Plan Number: 004**

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| **Year** | **Participant Contributions Transferred Late to Plan\*** | **Late Participant Loan Repayments Are Included** | **Contributions Not Corrected\*\*** | **Contributions Corrected Outside of VFCP** | **Total Fully Corrected Under VFCP and PTE 2002-51** |
| 2024 | $17611 | Yes | $17611 | $– $– $|  |

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\*&nbsp;&nbsp;&nbsp;&nbsp;Amount includes participant loan repayments.

\*\*&nbsp;&nbsp;&nbsp;&nbsp;Amount represents late contributions that were remitted to the Plan on October 4, 2024. The lost earnings were deposited into the Plan in June 2025. The Plan Sponsor plans to correct the late contributions under the Self-Correction Component of the Department of Labor's Voluntary Fiduciary Correction Program ("VFCP").

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**FEDERAL SIGNAL CORPORATION RETIREMENT SAVINGS PLAN**

**SCHEDULE H, LINE 4i – SCHEDULE OF ASSETS (HELD AT END OF YEAR)** 

December 31, 2024

**EIN: 36-1063330**

**Plan Number: 004**

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| | | | | |
|:---|:---|:---|:---|:---|
| **(a)** | **(b)**<br>**Identity of issue, borrower, lessor or similar party** | **(c)**<br>**Description of investments including maturity date, rate of interest, collateral, par or maturity value** | **(d)**<br>**Cost** | **(e)**<br>**Current value** |
| \* | Vanguard PRIMECAP Fund | Mutual fund | (1) | $76886690 |
| \* | Vanguard Institutional Index Fund | Mutual fund | (1) | 63733243 |
| \* | Federal Signal Stock Fund | Common stock fund | (1) | 57362704 |
| \* | Vanguard Retirement Savings Trust III | Common/collective trust | (1) | 48052171 |
| \* | Vanguard Institutional Target Retirement 2030 Trust II | Common/collective trust | (1) | 40200913 |
| \* | Vanguard Institutional Target Retirement 2025 Trust II | Common/collective trust | (1) | 34112926 |
| \* | Vanguard Institutional Target Retirement 2035 Trust II | Common/collective trust | (1) | 30637517 |
| \* | Vanguard Institutional Target Retirement 2045 Trust II | Common/collective trust | (1) | 29501500 |
| \* | Vanguard Institutional Target Retirement 2040 Trust II | Common/collective trust | (1) | 27437921 |
| \* | Vanguard Institutional Target Retirement 2050 Trust II | Common/collective trust | (1) | 19935065 |
| \* | Vanguard Explorer Fund | Mutual fund | (1) | 19781266 |
| \* | Vanguard Total Bond Market Index Fund | Mutual fund | (1) | 13291308 |
| \* | Vanguard Institutional Target Retirement 2055 Trust II | Common/collective trust | (1) | 12868134 |
| \* | Vanguard International Growth Fund | Mutual fund | (1) | 10668878 |
| \* | Vanguard Institutional Target Retirement 2020 Trust II | Common/collective trust | (1) | 10408188 |
| \* | Vanguard Small-Cap Value Index Fund | Mutual fund | (1) | 9951901 |
| \* | Vanguard Institutional Target Retirement 2060 Trust II | Common/collective trust | (1) | 8405027 |
| \* | Vanguard Institutional Target Retirement Income Trust II | Common/collective trust | (1) | 7382896 |
| \* | Vanguard Institutional Target Retirement 2065 Trust II | Common/collective trust | (1) | 4765394 |
| \* | Vanguard Mid-Cap Index Fund Admiral Shares | Mutual fund | (1) | 3555894 |
| \* | Dodge & Cox Income Fund Class X | Mutual fund | (1) | 3401674 |
| \* | Vanguard Institutional Target Retirement 2070 Trust II | Common/collective trust | (1) | 1194402 |
| \* | DFA Emerging Markets Core Equity Portfolio Institutional Class | Mutual fund | (1) | 738854 |
| \* | Vanguard Cash Reserve Federal Money Market Fund | Mutual fund | (1) | 222809 |
|  |  |  |  | 534497275 |
| \* | Participants' loans | Interest rates from 4.25% to 9.50% |  | 7122012 |
|  |  |  |  | $541619287 |

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**\*&nbsp;&nbsp;&nbsp;&nbsp;**Party-in-interest as defined by ERISA

(1)&nbsp;&nbsp;&nbsp;&nbsp;Cost information may be omitted for plan assets which are participant-directed.

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**EXHIBIT INDEX** 

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| | |
|:---|:---|
| **Exhibit No.** | **Description** |
| 23.1 | <u>[CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM](fss-202411kexhibit231.htm)</u> |

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**SIGNATURES** 

Pursuant to the requirements of the Securities Exchange Act of 1934, the Benefits Administration Committee has duly caused this annual report to be signed on its behalf by the undersigned hereunto duly authorized.

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| | | |
|:---|:---|:---|
| | | Federal Signal Corporation Retirement Savings Plan |
| Date: | June 27, 2025 | /s/ Lisa Baran |
|  |  | Lisa Baran |
|  |  | *Vice President, Human Resources<br>(Benefits Administration Committee)* |
|  |  | /s/ Diane I. Bonina |
|  |  | Diane I. Bonina |
|  |  | *Vice President, General Counsel and Secretary<br>(Federal Signal Corporation)* |

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## Exhibit 23.1

**Exhibit 23.1**

**CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM** 

We hereby consent to the incorporation by reference in registration statements (Form S-8 No. 333-228197 and No. 333-190976) pertaining to Federal Signal Corporation of our report dated June 27, 2025, relating to the statement of net assets available for benefits of Federal Signal Corporation Retirement Savings Plan as of December 31, 2024, the related statement of changes in net assets available for benefits for the year then ended, and the related supplemental information as of and for the year ended December 31, 2024, included in this Annual Report on Form 11-K of Federal Signal Corporation Retirement Savings Plan for the year ended December 31, 2024.

/s/ REHMANN ROBSON LLC

Grand Rapids, Michigan

June 27, 2025

<br>