1000 Alfred Nobel Drive Hercules, California 94547 (510) 724-7000

Norman D. Schwartz, Chief Executive Officer and Chairman of the Board of Directors of Bio-Rad, Steven D. Schwartz, an employee of Bio-Rad, Blue Raven Partners, L.P. (the "Partnership"), a California limited partnership organized to provide consolidated management of certain assets owned by the partners, and the Alice N. Schwartz Revocable Trust.

During the last five years, none of Norman D. Schwartz, Steven D. Schwartz, the Partnership and the Alice N. Schwartz Revocable Trust has been convicted in a criminal proceeding (excluding traffic violations and similar misdemeanors) or has been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

United States of America

Item 3 to the Schedule 13D is hereby amended, in pertinent part, as follows: Norman D. Schwartz Due to the death of Alice N. Schwartz, Norman D. Schwartz acquired beneficial ownership of the shares held in the David Schwartz Non-Exempt Marital Trust and the Alice N. Schwartz Revocable Trust, as he became the sole trustee of such trusts upon the death of his mother. Since the most recent filing of a statement on Schedule 13D, the following transactions have been effected by Norman D. Schwartz. Date: 8/26/2022*; Shares: 15,501; Type: Stock option exercise; Price: $107.32; Ownership: Direct Date: 11/7/2022 ; Shares: 84; Type: Gift; Price: --; Ownership: Direct Date: 8/25/2023*; Shares: 13,611; Type: Stock option exercise; Price: $117.50; Ownership: Direct Date: 11/1/2023*; Shares: 9,358; Type: Stock option exercise; Price: $119.80; Ownership: Direct Date: 11/1/2023*; Shares: 3,726; Type: Stock option exercise; Price: $139.56; Ownership: Direct Date: 11/1/2023*; Shares: 2,976; Type: Stock option exercise; Price: $159.32; Ownership: Direct Date: 12/5/2023 ; Shares: 98; Type: Gift; Price: --; Ownership: Direct Date: 8/26/2024 ; Shares: 114; Type: Gift; Price: --; Ownership: Direct Footnotes * Acquired through net share settlement. The shares of Class B Common Stock acquired on November 7, 2022, December 5, 2023 and August 26, 2024 were acquired by Norman D. Schwartz and his wife in equal amounts of one half each by gift from the Alice N. Schwartz Revocable Trust. Steven D. Schwartz Since the most recent filing of a statement on Schedule 13D, the following transactions have been effected by Steven D. Schwartz. Date: 11/7/2022 ; Shares: 84; Type: Gift; Price: --; Ownership: Direct Date: 12/5/2023 ; Shares: 98; Type: Gift; Price: --; Ownership: Direct Date: 8/26/2024 ; Shares: 114; Type: Gift; Price: --; Ownership: Direct The shares of Class B Common Stock acquired on November 7, 2022, December 5, 2023 and August 26, 2024 were acquired by Steven D. Schwartz and his wife in equal amounts of one half each by gift from the Alice N. Schwartz Revocable Trust. Alice N. Schwartz Revocable Trust Since the most recent filing of a statement on Schedule 13D, the following transactions have been effected by the Alice N. Schwartz Revocable Trust. Date: 11/7/2022 ; Shares: (252); Type: Gift; Price: --; Ownership: Direct Date: 12/5/2023 ; Shares: (294); Type: Gift; Price: --; Ownership: Direct Date: 8/26/2024 ; Shares: (342); Type: Gift; Price: --; Ownership: Direct

Item 4 to the Schedule 13D is hereby amended, in pertinent part, as follows: The purpose of the Shareholders' ownership of Bio-Rad shares has been control of the Company. The Shareholders control the management of the Company and may be deemed to be "parents" of the Company as that term is defined in the Rules and Regulations of the Commission.

Item 5 to the Schedule 13D is hereby amended, in pertinent part, as follows: (a)-(b) The Partnership: The Partnership is the direct and beneficial owner of 4,060,054 shares of the Class B Common Stock with respect to which it has sole voting and dispositive power, representing 80.1% of the issued and outstanding Class B Common Stock. Norman D. Schwartz and Steven D. Schwartz: Norman D. Schwartz and Steven D. Schwartz have indirect beneficial ownership of the 4,060,054 shares of Class B Common Stock held by the Partnership, over which they have shared voting and dispositive power, as the result of their positions as general partners in the Partnership. Norman D. Schwartz is the beneficial owner of 868,982 shares of Class B Common Stock. 494,510 of such shares of Class B Common Stock are held in the following trusts, both of which Mr. Schwartz is the sole trustee: the David Schwartz Non-Exempt Marital Trust (57,000 shares); and the Alice N. Schwartz Revocable Trust (437,510 shares). Prior to her death, Alice N. Schwartz was the sole trustee of the aforementioned trusts. Upon her death, Norman D. Schwartz became the sole trustee of such trusts. In addition, Mr. Schwartz holds 374,472 shares of Class B Common Stock but disclaims beneficial ownership with respect to 13,006 of such shares owned by Mr. Schwartz's wife. As a result of the foregoing, Mr. Schwartz is deemed to have beneficial ownership of an aggregate of 4,929,036 shares of Class B Common Stock, representing 97.2% of the issued and outstanding Class B Common Stock. Steven D. Schwartz holds 38,240 shares of Class B Common Stock but disclaims beneficial ownership with respect to 13,006 of such shares owned by Steven D. Schwartz's wife. As a result of the foregoing, Steven D. Schwartz is deemed to have beneficial ownership of an aggregate of 4,098,294 shares of Class B Common Stock, representing 80.8% of the issued and outstanding Class B Common Stock. The Alice N. Schwartz Revocable Trust is the direct and beneficial owner of 437,510 shares of Class B Common Stock with respect to which it has sole voting and dispositive power, representing 8.6% of the issued and outstanding Class B Common Stock. All percentages reported herein with respect to Class B Common Stock are calculated based upon 5,070,184 shares of Class B Common Stock outstanding as of July 28, 2025, as reported in the Issuer's Quarterly Report on Form 10-Q, filed with the Securities and Exchange Commission on July 31, 2025.

Not applicable

Not applicable

Due to the death of Mrs. Alice N. Schwartz, on September 25, 2025, Ms. Schwartz ceased to be a beneficial owner of more than 5% of the outstanding shares of Class B Common Stock of the Company.

Item 6 to the Schedule 13D is hereby amended, in pertinent part, as follows: Norman D. Schwartz owns beneficially 3,228,922 shares of Class A Common Stock, representing 14.6% of the issued and outstanding Class A Common Stock. 2,714,928 of these shares are held by the following trusts, all of which Norman D. Schwartz is the sole trustee: the David and Alice N. Schwartz Charitable Remainder Unitrust (34,311 shares); the David Schwartz Exemption Trust (90 shares); the David Schwartz Exempt Marital Trust (240 shares); the David Schwartz Non-Exempt Marital Trust (898,931 shares); and the Alice N. Schwartz Revocable Trust (1,781,356 shares). 17,145 of these shares are held by the Alles Institute for Medical Research, a Delaware Charitable Nonstock Corporation, with respect to which Norman D. Schwartz shares voting and dispositive power consistent with the purposes of the Delaware Charitable Nonstock Corporation. Steven D. Schwartz holds 380,789 shares of Class A Common Stock, but disclaims beneficial ownership with respect to 1,498 of such shares owned by Steven D. Schwartz's wife. Steven D. Schwartz's shares of Class A Common Stock represent approximately 1.7% of the issued and outstanding Class A Common Stock. 17,145 of these shares are held by the Alles Institute for Medical Research, a Delaware Charitable Nonstock Corporation, with respect to which Steven D. Schwartz shares voting and dispositive power consistent with the purposes of the Delaware Charitable Nonstock Corporation. The Alice N. Schwartz Revocable Trust holds 1,781,356 shares of Class A Common Stock, representing 8.2% of the issued and outstanding Class A Common Stock. Norman D. Schwartz and Steven D. Schwartz are brothers. By virtue of the Shareholders' Class B Common Stock ownership, they control the management of the Company and may be deemed to be "control persons" of the Company as that term is defined in the Rules and Regulations of the Commission. All percentages reported herein with respect to Class A Common Stock are calculated based upon 21,992,307 shares of Class A Common Stock outstanding as of July 28, 2025, as reported in the Issuer's Quarterly Report on Form 10-Q, filed with the Securities and Exchange Commission on July 31, 2025. For Norman D. Schwartz, the beneficial ownership calculation with respect to Class A Common Stock is calculated by using a denominator of (a) 21,992,307 shares of Class A Common Stock plus (b) 53,415 shares of Class A Common Stock issuable upon the exercise of stock options exercisable by Mr. Schwartz immediately or within sixty days of September 25, 2025.

Exhibit 1 - Agreement Among the Shareholders to File Joint Schedule 13D Exhibit 2*- Limited Partnership Agreement of Blue Raven Partners, L.P. *Incorporated by reference to Exhibit 2 to our Schedule 13D filed with the Commission on January 13, 2000