LITTELFUSE INC /DE 10-K

ITEM 9A. CONTROLS AND PROCEDURES. Evaluation of Disclosure Controls and Procedures The Company maintains disclosure controls and procedures that are designed to ensure that information required to be disclosed in its reports filed under the Securities Exchange Act of 1934, as amended, is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms and that such information is accumulated and communicated to management, including the Company’s Chief Executive Officer and Chief Financial Officer, as appropriate, to allow for timely decisions regarding required disclosure. In designing and evaluating the disclosure controls and procedures, the Company recognizes that any controls and procedures, no matter how well designed and operated, can provide only 88 Table of Contents reasonable assurance of achieving the desired control objectives, and the Company is required to apply its judgment in evaluating the cost-benefit relationship of possible controls and procedures. As required by SEC Rule 15d-15(b), the Company carried out an evaluation, under the supervision and with the participation of its management, including the Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of its disclosure controls and procedures pursuant to SEC Rule 13a-15 as of the end of the period covered by this report. Based on the foregoing, the Company’s Chief Executive Officer and Chief Financial Officer concluded that the Company’s disclosure controls and procedures were effective as of December 26, 2020. Management’s Report on Internal Control over Financial Reporting Section 404 of the Sarbanes-Oxley Act of 2002 requires management to include in this Annual Report on Form 10-K a report on management’s assessment of the effectiveness of the Company’s internal control over financial reporting, as well as an attestation report from the Company’s independent registered public accounting firm on the effectiveness of the Company’s internal control over financial reporting. Management is responsible for establishing and maintaining adequate internal control over financial reporting as such term is defined in Exchange Act Rule 13a-15(f) and 15d-15(f). The Company’s internal control system was designed to provide reasonable assurance to its management and the Board of Directors regarding the preparation and fair presentation of published financial statements. All internal control systems, no matter how well designed, have inherent limitations. Therefore, even those systems determined effective can provide only reasonable assurance with respect to financial statement preparation and presentation. A material weakness is a deficiency, or a combination of deficiencies, in the internal control over financial reporting such that there is a reasonable possibility that a material misstatement of the annual or interim financial statement will not be prevented or detected on a timely basis. The Company’s management, including the its Principal Executive Officer and Principal Financial Officer, assessed the effectiveness of the Company’s internal control over financial reporting as of December 26, 2020, based upon the updated framework in Internal Control — Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (“COSO”) in 1992 and updated in May 2013. Based on this assessment, the Company’s management concluded that, as of December 26, 2020, the Company’s internal control over financial reporting was effective. Changes in Internal Control over Financial Reporting There has been no change in the Company’s internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) that occurred during the 12 months or fiscal quarter ended December 26, 2020, that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting. ITEM 9B. OTHER INFORMATION. None. 89 Table of Contents PART III ITEM 10. DIRECTORS, EXECUTIVE OFFICERS, AND CORPORATE GOVERNANCE. Except as set forth below, the information required by this item will be contained in the Company’s Proxy Statement related to our 2021 Annual Meeting of Stockholders (the "proxy statement") and is incorporated herein by reference. Information concerning directors and nominees for director is set forth in the section titled “Proposal No. 1 Election of Directors” in the Company’s proxy statement and is incorporated herein by reference. Information concerning the Company’s Audit Committee and Audit Committee financial expert is set forth in the sections titled "Board Committees" and “Director Independence; Financial Experts” in the Company's proxy statement and is incorporated herein by reference. Information concerning the procedures by which security holders may recommend nominees to the Company’s Board of Directors is set forth in the section titled “Director Nomination” in the Company’s proxy statement and is incorporated herein by reference. Information concerning compliance with Section 16 of the Securities Exchange Act of 1934 is set forth in the section titled “Delinquent Section 16(a) Reports” in the Company’s proxy statement and is incorporated herein by reference. Information regarding the Executive Officers of the Company can be found in Part I of this Annual Report on Form 10-K under the caption "Information about our Executive Officers." Code of Ethics The company has adopted a Code of Conduct (Code of Ethics) that applies to all of the Company’s employees including the Company’s Principal Executive Officer, Principal Financial Officer, Principal Accounting Officer and persons performing similar functions. It has posted the text of the Code of Conduct on its website at https://investor.littelfuse.com/corporate-governance/governance-overview and intends to disclose on such website any amendments to, or waivers from the Code of Conduct. The company’s website is not incorporated by reference into this Annual Report. ITEM 11. EXECUTIVE COMPENSATION. Information concerning compensation of the Company’s executive officers and directors for the fiscal year ended December 26, 2020, is set forth in the sections titled “Compensation Discussion & Analysis,” “Compensation Tables,” "Compensation Committee Report," "CEO Pay Ratio," "Potential Payments Upon Termination or Change in Control" and “Director Compensation” in the Company’s proxy statement and is incorporated herein by reference, except the section titled “Compensation Committee Report” is hereby “furnished” and not “filed” with this Annual Report on Form 10-K. Information concerning compensation committee interlocks is set forth in the section titled “Compensation Committee Interlocks and Insider Participation” in the Company’s proxy statement and is incorporated herein by reference. COMPENSATION PLAN INFORMATION We have two equity compensation plans that have been approved by our stockholders: the Littelfuse, Inc. Long-Term Incentive Plan that was approved by our stockholders at the April 2017 annual stockholder meeting and the Deferred Compensation Plan for Non-Employee Directors that was approved by our stockholders at the May 2005 annual stockholder meeting. Pursuant to our acquisition of IXYS Corporation on January 17, 2018, we assumed four equity compensation plans that have not been approved by our stockholders and pursuant to which we may continue to grant equity awards: IXYS Corporation 2009 Equity Incentive Plan, IXYS Corporation 2011 Equity Incentive Plan, IXYS Corporation 2013 Equity Incentive Plan, IXYS Corporation 2016 Equity Incentive Plan (together, the "IXYS Plans"). We also assumed two expired equity compensation plans that have not been approved by our stockholders and pursuant to which we have outstanding equity awards: the Zilog, Inc. 2002 Omnibus Stock Incentive Plan and Zilog, Inc. 2004 Omnibus Stock Incentive Plan (together the "Zilog Plans"). The IXYS Corporation 2009 Equity Incentive Plan expired in June 2019 and equity awards remain outstanding under it. 90 Table of Contents Information about our equity compensation plans that were either approved or not approved by our stockholders as of December 26, 2020, is as follows: Plan Category Number of securities to be issued upon exercise of outstanding options, warrants and rights Weighted-average exercise price of outstanding options, warrants, and rights (1) Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in the first column) Equity compensation plans approved by security holders 719,991 (2) $157.84 699,516 (4) Equity compensation plans not approved by security holders 129,913 (3) $104.49 206,617 (5) Total 849,904 $148.01 906,133 (1) The weighted average exercise price does not take into account the shares issuable upon the vesting of outstanding restricted stock units, which have no exercise price. (2) Includes 175,819 shares reserved for issuance upon vesting of outstanding restricted stock units and 544,172 outstanding stock options granted under the Littelfuse, Inc. Long-Term Incentive Plan. (3) Includes 7,136 shares reserved for issuance upon vesting of outstanding restricted stock units under the IXYS Plans and 122,777 outstanding stock options granted under the IXYS Plans and Zilog Plan. Below is a brief description of the material features of the compensation plans acquired pursuant to the acquisition of IXYS Corporation. (4) Includes 654,869 shares that remain available for future issuance under the Littelfuse, Inc. Long-Term Incentive Plan and 44,647 shares that remain available for future issuance under the Deferred Compensation Plan for Non-Employee Directors. (5) Includes 11,385 shares that remain available for future issuance under the IXYS Corporation 2011 Equity Incentive Plan, 26,689 shares that remain available for future issuance under the IXYS Corporation 2013 Equity Incentive Plan, and 168,543 shares that remain available for future issuance under the IXYS Corporation 2016 Equity Incentive Plan. IXYS Plans In connection with the acquisition of IXYS Corporation, we assumed the IXYS Corporation 2009 Equity Incentive Plan, IXYS Corporation 2011 Equity Incentive Plan, IXYS Corporation 2013 Equity Incentive Plan, IXYS Corporation 2016 Equity Incentive Plan and outstanding unvested stock options originally granted by IXYS Corporation under the IXYS Plans that were held by continuing employees. At the time of the acquisition of IXYS Corporation, these awards were converted to Littelfuse stock options, with adjustments made to the exercise price of the stock options and the number of shares subject to stock options as agreed upon in the Acquisition Agreement. These unvested options vest in accordance with their original terms, generally vesting in equal annual installments over a four-year period from the original grant date. The options, once granted, generally expire ten years from the date of grant. Under the IXYS Plans, we may grant to former employees of IXYS Corporation or its subsidiaries restricted stock awards, RSUs, stock options and stock appreciation rights with an exercise price that is no less than the fair market value on the date of grant. Equity awards granted under the IXYS Plans following the acquisition have been on similar terms and consistent with grants made pursuant to the Littelfuse, Inc Long-Term Incentive Plan. The IXYS Corporation 2009 Equity Incentive Plan expired in June 2019 and no additional grants were made after the expiration date. As of December 26, 2020, 206,617 shares remained available for issuance under the IXYS Plans. Zilog Plan In connection with the acquisition of IXYS Corporation, we assumed the Zilog, Inc. 2004 Omnibus Stock Incentive Plan and outstanding stock options originally granted by IXYS Corporation under the Zilog Plan that were held by continuing employees of Zilog. At the time of the acquisition of IXYS Corporation, these awards were converted to Littelfuse stock options, with adjustments made to the exercise price of the stock options and the number of shares subject to stock options as agreed upon in the Acquisition Agreement. These options vested in accordance with their original terms, generally in equal annual installments over a four-year period from the original grant date. The options generally expire ten years from the date of grant. The Zilog 2004 Omnibus Stock Incentive Plan expired in February 2014 and no additional grants have been made thereunder. Therefore, as of December 26, 2020, no shares remain available for issuance of new awards under the Zilog Plan and 20,499 stock options remain outstanding. 91 Table of Contents ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS. Information concerning the security ownership of certain beneficial owners, the Company’s directors and executive officers as of February 25, 2021, is set forth in the section titled “Ownership of Littelfuse, Inc. Common Stock” in the Company’s proxy statement and is incorporated herein by reference. ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS AND DIRECTOR INDEPENDENCE. Information concerning the independence of the Company’s directors, certain relationships and related transactions during 2020 and the Company’s policies with respect to such transactions is set forth in the sections titled "Director Independence; Financial Experts", “Related Person Transaction Policy”, “Related Party Transactions” and “Dr. Zommer Consulting Agreement” in the Company’s proxy statement and is incorporated herein by reference. ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES. Information concerning principal accountant fees and services is set forth in the section titled “Audit Related Matters” in the Company’s proxy statement and is incorporated herein by reference. 92 Table of Contents PART IV ITEM 15. EXHIBITS, FINANCIAL STATEMENT SCHEDULES. (a) Financial Statements and Schedules Page 1. The following Financial Statements are filed as a part of this report: i. Reports of Independent Registered Public Accounting Firms 43 - 45 ii. Consolidated Balance Sheets as of December 26, 2020 and December 28, 2019 46 iii. Consolidated Statements of Net Income for the fiscal years ended December 26, 2020, December 28, 2019 and December 29, 2018 47 vi. Consolidated Statements of Comprehensive Income for the fiscal years ended December 26, 2020, December 28, 2019 and December 29, 2018 48 v. Consolidated Statements of Cash Flows for the fiscal years ended December 26, 2020, December 28, 2019 and December 29, 2018 49 vi. Consolidated Statements of Equity for the fiscal years ended December 26, 2020, December 28, 2019 and December 29, 2018 50 vii. Notes to Consolidated Financial Statements 51 - 88 2. The following Financial Statement Schedule is submitted herewith for the periods indicated therein. i. Schedule II - Valuation and Qualifying Accounts and Reserves 94 All other schedules for which provision is made in the applicable accounting regulations of the Securities and Exchange Commission are not required under the related instructions or are inapplicable and, therefore, have been omitted. 3. Exhibits. See Exhibit Index 96 Item 16. FORM 10-K SUMMARY None. 93 Table of Contents SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS AND RESERVES Description Balance at Beginning of Year Charged to Costs and Expenses (a) Deductions (b) Other (c) Balance at End of Year (in thousands) Fiscal year ended December 26, 2020 Allowance for losses on accounts receivable $ 1,310 $ 1,170 $ ( 329 ) $ ( 751 ) $ 1,400 Reserves for sales discounts and allowances $ 40,733 $ 113,709 $ ( 112,401 ) $ 1,796 $ 43,837 Fiscal year ended December 28, 2019 Allowance for losses on accounts receivable $ 1,062 $ 410 $ ( 172 ) $ 10 $ 1,310 Reserves for sales discounts and allowances $ 34,976 $ 133,434 $ ( 127,330 ) $ ( 347 ) $ 40,733 Fiscal year ended December 29, 2018 Allowance for losses on accounts receivable $ 1,172 $ 319 $ ( 557 ) $ 128 $ 1,062 Reserves for sales discounts and allowances $ 26,344 $ 124,638 $ ( 118,438 ) $ 2,432 $ 34,976 (a) Includes provision for doubtful accounts, sales returns and sales discounts granted to customers. (b) Represents uncollectible accounts written off, net of recoveries and credits issued to customers. (c) Represents business acquisitions and foreign currency translation adjustments. 94 Table of Contents SIGNATURES Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. Littelfuse, Inc. By: /s/ David W. Heinzmann David W. Heinzmann, President and Chief Executive Officer Date: February 18, 2021 Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant on February 18, 2021 and in the capacities indicated. /s/ Gordon Hunter Chairman of the Board of Directors Gordon Hunter /s/ David W. Heinzmann Director, President and Chief Executive Officer David W. Heinzmann (Principal Executive Officer) /s/ Kristina A. Cerniglia Director Kristina A. Cerniglia /s/ Tzau-Jin Chung Director Tzau-Jin Chung /s/ Cary T. Fu Director Cary T. Fu /s/ Anthony Grillo Director Anthony Grillo /s/ John E. Major Director John E. Major /s/ William P. Noglows Director William P. Noglows /s/ Maria C. Green Director Maria C. Green Director Nathan Zommer /s/ Meenal A. Sethna Executive Vice President and Chief Financial Officer Meenal A. Sethna (Principal Financial Officer) /s/ Jeffrey G. Gorski Corporate Controller and Chief Accounting Officer Jeffrey G. Gorski (Principal Accounting Officer) 95 Table of Contents EXHIBIT INDEX The following documents listed below that have been previously filed with the SEC (1934 Act File No. 0-20388) are incorporated herein by reference: Incorporated by Reference Herein Exhibit No. Description Form Exhibit Filing Date File No. 2.1 Agreement and Plan of Merger, dated August 25, 2017, as amended by Amendment No. 1, dated December 4, 2017, by and among IXYS Corporation, Littelfuse, Inc., Iron Merger Co., Inc., and IXYS Merger Co., LLC. S-4/A Annex A 12/11/2017 333-22114 3.1 Certificate of Incorporation dated November 25, 1991, as amended April 25, 1997. 10-K 3.1 2/27/2017 0-20388 3.2 Certificate of Designations of Series A Preferred Stock. 8-K 4.2 12/1/1995 0-20388 3.3 Bylaws, as amended and restated January 24, 2019. 8-K 3.1 1/25/2019 0-20388 4.1 Description of Securities of Littelfuse, Inc. 10-K 4.1 2/21/2020 0-20388 10.1 Form of Stock Option Award Agreement under the Littelfuse, Inc. Outside Directors' Equity Plan.++ 8-K 99.3 5/1/2008 0-20388 10.2 Form of Restricted Stock Unit Award Agreement under the Littelfuse, Inc. Outside Directors' Equity Plan.++ 8-K 99.4 5/1/2008 0-20388 10.3 Form of Stock Option Award Agreement under the Littelfuse, Inc. Equity Incentive Compensation Plan .++ 8-K 10.2 4/28/2009 0-20388 10.4 Form of Restricted Stock Unit Award Agreement (Outside Director) under the Littelfuse, Inc. Long-Term Incentive Plan.++ S-8 4.4 5/19/2010 0-20388 10.5 Form of Stock Option Award Agreement under the Littelfuse, Inc. Long-Term Incentive Plan.++ S-8 4.6 5/19/2010 0-20388 10.6 Littelfuse, Inc. Annual Incentive Plan, effective January 1, 2014. ++ DEF14A A 3/17/2014 0-20388 10.7 Form of Restricted Stock Unit Award Agreement (Executive) under the Littelfuse, Inc. Long-Term Incentive Plan.++ 10-Q 10.2 7/31/2015 0-20388 10.8 Form of Restricted Stock Unit Award Agreement (Tier II Management) under the Littelfuse, Inc. Long-Term Incentive Plan.++ 10-Q 10.3 7/31/2015 0-20388 10.9 Form of Stock Option Award Agreement (Executive) under the Littelfuse, Inc. Long-Term Incentive Plan. ++ 10-Q 10.3 5/6/2016 0-20388 10.10 Form of Stock Option Award Agreement (Outside Director – 2016 Grant) under the Littelfuse, Inc. Long-Term Incentive Plan. ++ 10-Q 10.4 5/6/2016 0-20388 10.11 Form of Restricted Stock Unit Award Agreement (Executive) under the Littelfuse, Inc. Long-Term Incentive Plan. ++ 10-Q 10.5 5/6/2016 0-20388 10.12 Form of Restricted Stock Unit Award Agreement (Tier II Management) under the Littelfuse, Inc. Long-Term Incentive Plan. ++ 10-Q 10.6 5/6/2016 0-20388 10.13 Form of Restricted Stock Unit Award Agreement (Outside Director – 2016 Grant) under the Littelfuse, Inc. Long-Term Incentive Plan. ++ 10-Q 10.7 5/6/2016 0-20388 10.14 Letter Agreement entered into between Littelfuse, Inc. and David W. Heinzmann. Effective January 1, 2017. ++ 8-K 10.2 11/16/2016 0-20388 10.15 Littelfuse, Inc. 3.03% Senior Note, Series A, due February 15, 2022, and 3.74% Senior Note, Series B, due February 15, 2027 Note Purchase Agreement. 8-K 10.1 12/9/2016 0-20388 10.16 Littelfuse, Netherland C.V. 1.14% Senior Note, Series A, due December 8, 2023, and 1.83% Senior Note, Series B, due December 8, 2028 Note Purchase Agreement. 8-K 10.2 12/9/2016 0-20388 96 Table of Contents Incorporated by Reference Herein Exhibit No. Description Form Exhibit Filing Date File No. 10.17 Subsidiary Guaranty Agreement, dated December 8, 2016. 8-K 10.4 12/9/2016 0-20388 10.18 Subsidiary Guaranty Agreement, dated as of February 15, 2017. 8-K 10.2 2/15/2017 0-20388 10.19 Restated Littelfuse, Inc. Supplemental Retirement and Savings Plan, effective January 1, 2017. ++ 10-K 10.50 2/27/2017 0-20388 10.20 Amended and Restated Littelfuse, Inc. Long-Term Incentive Plan. ++ 8-K 10.1 5/1/2017 0-20388 10.21 Form of 2017 Restricted Stock Unit Award Agreement. ++ 8-K 10.2 5/1/2017 0-20388 10.22 Form of 2017 Stock Option Award Agreement. ++ 8-K 10.3 5/1/2017 0-20388 10.23 Employment offer letter between Littelfuse, Inc. and Jeffrey Gorski, dated June 28, 2017. ++ 8-K 10.1 8/14/2017 0-20388 10.24 U.S. Subsidiary Guarantor Supplement, dated as of October 13, 2017, made by Iron Merger Co., Inc. in favor of the note purchasers and the other holders. 8-K 10.5 10/16/2017 0-20388 10.25 U.S. Subsidiary Guarantor Supplement, dated as of October 13, 2017, made by IXYS Merger Co., LLC in favor of the note purchasers and the other holders. 8-K 10.6 10/16/2017 0-20388 10.26 Cross Border Subsidiary Guarantor Supplement, dated as of October 13, 2017, made by Iron Merger Co., Inc. in favor of the note purchasers and the other holders. 8-K 10.7 10/16/2017 0-20388 10.27 Cross Border Subsidiary Guarantor Supplement, dated as of October 13, 2017, made by IXYS Merger Co., LLC in favor of the note purchasers and the other holders. 8-K 10.8 10/16/2017 0-20388 10.28 Note Purchase Agreement, dated November 15, 2017, among Littelfuse, Inc. and note purchasers listed on the signature pages thereto. 8-K 10.1 11/15/2017 0-20388 10.29 Form of 3.78% Senior Note, Series B, due February 15, 2030. 8-K 4.2 11/15/2017 0-20388 10.30 Form of 3.48% Senior Note, Series A, due February 15, 2025, 8-K 4.1 11/15/2017 0-20388 10.31 Subsidiary Guaranty Agreement, dated as of January 16, 2018, made by LFUS LLC, Littelfuse Commercial Vehicle, LLC, Iron Merger Co., Inc., IXYS Merger Co., LLC and SymCom, Inc. in favor of the note purchasers and the other holders. 8-K 10.2 1/18/2018 0-20388 10.32 Littelfuse, Inc. Executive Severance Policy. ++ 8-K 10.4 1/18/2018 0-20388 10.33 Form of Indemnity Agreement between Nathan Zommer and IXYS Corporation. ++ 10-K 10.3 6/12/2008 000-26124 10.34 IXYS Corporation 2009 Equity Incentive Plan++ S-8 4.4 1/19/2018 333-221147 10.35 IXYS Corporation 2011 Equity Incentive Plan++ S-8 4.5 1/19/2018 333-221147 10.36 IXYS Corporation 2013 Equity Incentive Plan++ S-8 4.6 1/19/2018 333-221147 10.37 IXYS Corporation 2016 Equity Incentive Plan++ S-8 4.7 1/19/2018 333-221147 10.38 Zilog, Inc. 2002 Omnibus Stock Incentive Plan++ S-8 4.8 1/19/2018 333-221147 10.39 Zilog, Inc. 2004 Omnibus Stock Incentive Plan++ S-8 4.9 1/19/2018 333-221147 10.40 Notice of Stock Option Grant and Agreement for the IXYS Corporation 2009 Equity Incentive Plan++ 10-Q 10.4 8/10/2009 000-26124 10.41 Form of Nonqualified Stock Option Agreement for Stock Options pursuant to the Zilog, Inc. 2004 Omnibus Stock Incentive Plan++ 10-K 10.28 6/11/2010 000-26124 10.42 Notice of Stock Option Grant and Agreement for IXYS Corporation 2011 Equity Incentive Plan++ 10-Q 10.2 8/5/2011 000-26124 10.43 Notice of Stock Option Grant and Agreement for IXYS Corporation 2013 Equity Incentive Plan++ 10-Q 10.6 8/9/2013 000-26124 10.44 Notice of Stock Option Grant and Agreement for IXYS Corporation 2016 Equity Incentive Plan++ 10-Q 10.1 11/3/2016 000-26124 97 Table of Contents Incorporated by Reference Herein Exhibit No. Description Form Exhibit Filing Date File No. 10.45 U.S. Subsidiary Guarantor Supplement, dated as of March 14, 2018, made by Clare Capital, Inc., Clare Components, Inc., Clare Electronics, Inc., Clare Instruments, Inc., Clare Services, Inc., Clare Technologies, Inc., Directed Energy, Inc., IXYS Buckeye, LLC, IXYS Integrated Circuits Division AV Inc., IXYS Integrated Circuits Divisions Inc., IXYS Long Beach, Inc., IXYS USA, Inc., Microwave Technology, Inc., Pele Technology, Inc., Reaction Technology Incorporation and Zilog, Inc. in favor of the note purchasers and the other holders. 10-Q 10.2 05/02/2018 0-20388 10.46 Cross Border Subsidiary Guarantor Supplement, dated as of March 14, 2018, made by Clare Capital, Inc., Clare Components, Inc., Clare Electronics, Inc., Clare Instruments, Inc., Clare Services, Inc., Clare Technologies, Inc., Directed Energy, Inc., IXYS Buckeye, LLC, IXYS Integrated Circuits Division AV Inc., IXYS Integrated Circuits Divisions Inc., IXYS Long Beach, Inc., IXYS USA, Inc., Microwave Technology, Inc., Pele Technology, Inc., Reaction Technology Incorporation and Zilog, Inc. in favor of the note purchasers and the other holders. 10-Q 10.3 05/02/2018 0-20388 10.47 Note Purchase Agreement Subsidiary Guarantor Supplement, dated as of March 14, 2018, made by Clare Capital, Inc., Clare Components, Inc., Clare Electronics, Inc., Clare Instruments, Inc., Clare Services, Inc., Clare Technologies, Inc., Directed Energy, Inc., IXYS Buckeye, LLC, IXYS Integrated Circuits Division AV Inc., IXYS Integrated Circuits Divisions Inc., IXYS Long Beach, Inc., IXYS USA, Inc., Microwave Technology, Inc., Pele Technology, Inc., Reaction Technology Incorporation and Zilog, Inc. in favor of the note purchasers and the other holders. 10-Q 10.4 05/02/2018 0-20388 10.48 U.S. Subsidiary Guarantor Supplement, dated as of August 22, 2018, made by Reaction Technology Epi, LLC and Reaction Tech RE, LLC in favor of the note purchasers and the other holders. 10-Q 10.3 10/31/2018 0-20388 10.49 Cross Border Subsidiary Guarantor Supplement, dated as of August 22, 2018, made by Reaction Technology Epi, LLC and Reaction Tech RE, LLC in favor of the note purchasers and the other holders. 10-Q 10.4 10/31/2018 0-20388 10.50 Note Purchase Agreement Subsidiary Guarantor Supplement, dated as of August 22, 2018, made by Reaction Technology Epi, LLC and Reaction Tech RE, LLC in favor of the note purchasers and the other holders. 10-Q 10.5 10/31/2018 0-20388 10.51 U.S. Subsidiary Guarantor Supplement, dated as of October 22, 2018, made by Littelfuse International Holding, LLC, Littelfuse Holding, LLC and Monolith Semiconductor, Inc. in favor of the note purchasers and the other holders. 10-K 10.104 02/22/2019 0-20388 10.52 U.S. (November 2017) Subsidiary Guarantor Supplement, dated as of October 22, 2018, made by Littelfuse International Holding, LLC, Littelfuse Holding, LLC and Monolith Semiconductor, Inc. in favor of the note purchasers and the other holders. 10-K 10.105 02/22/2019 0-20388 10.53 Cross Border Assumption Agreement, dated as of October 3, 2018, made by each of New Dutch B.V. and IXYS Dutch B.V. in favor of the note purchasers and the other holders. 10-K 10.106 02/22/2019 0-20388 10.54 Cross Border Subsidiary Guarantor Supplement, dated as of October 22, 2018, made by Littelfuse International Holding, LLC, Littelfuse Holding, LLC and Monolith Semiconductor, Inc. in favor of the note purchasers and the other holders. 10-K 10.107 02/22/2019 0-20388 10.55 Amended and Restated Employment Agreement entered into between Littelfuse Europe GmbH and Alexander Conrad, effective April 1, 2019. ++ 10-K 10.77 02/21/2020 0-20388 98 Table of Contents Incorporated by Reference Herein Exhibit No. Description Form Exhibit Filing Date File No. 10.56 Amended and Restated Credit Agreement, dated as of April 3, 2020, by and among Littelfuse, Inc., certain subsidiaries of the company, as designated borrowers, certain subsidiaries of the company, as guarantors, the lenders party thereto and Bank of America, N.A., as agent, JPMorgan Chase Bank, N.A., as syndication agent, PNC Bank, National Association, as senior documentation agent, BMO Harris Bank, N.A. and Wells Fargo Bank, National Association, as co-documentation agents, BofA Securities, Inc. as sole bookrunner and joint lead arranger, and JPMorgan Chase Bank, N.A., as joint lead arranger . 8-K 10.1 4/7/2020 0-20388 10.57 Form of Restricted Stock Unit Award Agreement (Tier I) under the Littelfuse, Inc. Long-Term Incentive Plan. ++ 8-K 10.1 4/24/2020 0-20388 10.58 Form of Option Award Agreement (Tier I) under the Littelfuse, Inc. Long-Term Incentive Plan. ++ 8-K 10.2 4/24/2020 0-20388 10.59 Form of Restricted Stock Unit Award Agreement (Non-Employee Director) under the Littelfuse, Inc. Long-Term Incentive Plan. ++ 8-K 10.3 4/24/2020 0-20388 10.60 Form of Option Award Agreement (Non-Employee Director) under the Littelfuse, Inc. Long-Term Incentive Plan. + + 8-K 10.4 4/24/2020 0-20388 10.61 Form of Restricted Stock Unit Award Agreement (Tier II) under the Littelfuse, Inc. Long-Term Incentive Plan. ++ 10-Q 10.6 4/29/2020 0-20388 10.62 Form of Restricted Stock Unit Award Agreement (IXYS Tier II) under the IXYS Corporation Equity Incentive Plan . ++ 10-Q 10.7 4/29/2020 0-20388 10.63 Form of Retention Stock Option Award Agreement under the Littelfuse, Inc. Long-Term Incentive Plan . ++ 10-Q 10.8 7/29/2020 0-20388 10.64 Form of Retention Stock Option Award Agreement under the IXYS Corporation Equity Incentive Plan . ++ 10-Q 10.9 7/29/2020 0-20388 10.65 Form of Retention Restricted Stock Unit Award Agreement under the Littelfuse, Inc. Long-Term Incentive Plan . ++ 10-Q 10.10 7/29/2020 0-20388 10.66 Form of Retention Restricted Stock Unit Award Agreement under the IXYS Corporation Equity Incentive Plan . ++ 10-Q 10.11 7/29/2020 0-20388 10.67 Amended and Restated Littelfuse Deferred Compensation Plan for Non-Employee Directors . ++ 10-Q 10.1 10/28/2020 0-20388 10.68* First Amendment to the Littelfuse, Inc. Supplemental Retirement and Savings Plan, effective January 1, 2019 .++ 10.69* Second Amendment to the Littelfuse, Inc. Supplemental Retirement and Savings Plan, effective January 1, 2020 .++ 10.70* Third Amendment to the Littelfuse, Inc. Supplemental Retirement and Savings Plan, effective January 1, 2020. ++ 10.71* Form Tier I Change of Control Agreement, effective January 1, 2021. ++ 10.72* Form Tier II Change of Control Agreement, effective January 1, 2021 .++ 10.73* Summary of Non-Employee Director Compensation. ++ 21.1* Subsidiaries . 23.1* Consent of Independent Registered Public Accounting Firm . 31.1* Certification of Chief Executive Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. 31.2* Certification of Chief Financial Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. 32.1+++ Certification of the Chief Executive Officer and Chief Financial Officer Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. 99 Table of Contents Incorporated by Reference Herein Exhibit No. Description Form Exhibit Filing Date File No. 101.INS* XBRL Instance Document. 101.SCH* XBRL Taxonomy Extension Schema Document. 101.CAL* XBRL Taxonomy Extension Calculation Linkbase Document. 101.LAB* XBRL Taxonomy Extension Label Linkbase Document. 101.PRE* XBRL Taxonomy Extension Presentation Linkbase Document. 101.DEF* XBRL Taxonomy Extension Definition Linkbase Document. 104 The cover page on this Annual Report on Form 10-K for the fiscal year ended December 26, 2020, formatted in Inline XBRL and contained in Exhibit 101. * Filed with this Report. + Exhibits and schedules omitted pursuant to Item 601(b)(2) of Regulation S-K. Littelfuse agrees to furnish a supplemental copy of an omitted exhibit or schedule to the SEC upon request. ++ Management contract or compensatory plan or arrangement. +++ Furnished with this Report. 100