As previously disclosed, on October 28, 2025, Olympic Steel, Inc., an Ohio corporation (the “Company”), entered into an Agreement and Plan of
Merger (the “Merger Agreement”) with Ryerson Holding Corporation, a Delaware corporation (“Ryerson”), and Crimson MS Corp., an Ohio corporation and a wholly owned subsidiary of Ryerson (“Merger Sub” and, together
with Ryerson, the “Parent Parties”). The Merger Agreement provides that, subject to the terms and conditions set forth therein, Merger Sub will merge with and into the Company (the “Merger”), with the Company continuing as
the surviving corporation and a wholly owned subsidiary of Ryerson. On December 5, 2025, Ryerson filed a registration statement on Form S-4 that includes a joint proxy statement of Ryerson and Olympic and
a prospectus of Ryerson (as amended, the “Joint Proxy Statement/Prospectus”). On January 14, 2026, the Company filed with the Securities and Exchange Commission (the “SEC”) a definitive proxy statement with respect to
the special meeting of the Company’s shareholders in connection with the Merger scheduled to be held on February 12, 2026, at 9:30 a.m. Eastern Time, via live audio-only webcast (the “Special Meeting”).
In connection with the Merger, 14 demand letters have been received by the Company sent on behalf of, and two complaints have been
filed on behalf of, purported shareholders of the Company challenging the adequacy of certain disclosures made in the Joint Proxy Statement/Prospectus (collectively, the “Shareholder Actions”). The two complaints were both filed in the
Supreme Court of the State of New York, County of New York, and are captioned Weiss v. Olympic Steel, Inc. et al., Index No. 650390/2026 (N.Y. Sup. Ct. Jan. 21, 2026) and Hamilton v. Olympic Steel, In. et al., Index
No. 650412/2026 (N.Y. Sup. Ct. Jan. 22, 2026). The Company and Ryerson believe that the allegations in the Shareholder Actions are without merit.
The Company and Ryerson deny that the Joint Proxy Statement/Prospectus is deficient in any respect. The Company denies that it has violated any laws or
breached any duties to the Company’s shareholders, denies all allegations in the Shareholder Actions, and believes no supplemental disclosure to the Joint Proxy Statement/Prospectus was or is required under any applicable law, rule, or
regulation. However, solely to eliminate the burden and expense of potential litigation, to moot plaintiffs’ unmeritorious disclosure claims, and to avoid potential delay or disruption to the Merger, the Company and Ryerson have determined to
voluntarily supplement the Joint Proxy Statement/Prospectus with the below disclosures. The Company and Ryerson believe that the disclosures set forth in the Joint Proxy Statement/Prospectus comply fully with applicable law and nothing in the below
supplemental disclosures will be deemed an admission of the legal necessity or materiality under applicable law of any of the disclosures set forth herein.
To the extent that information in the below supplemental disclosures differs from, or updates information contained in, the Joint Proxy Statement/Prospectus,
the information in the below supplemental disclosures will supersede or supplement the information in the Joint Proxy Statement/Prospectus. Except as otherwise described in the below supplemental disclosures, the Joint Proxy Statement/Prospectus,
the annexes to the Joint Proxy Statement/Prospectus and the documents referred to, contained in or incorporated by reference in the Joint Proxy Statement/Prospectus are not otherwise modified, supplemented or amended.
Supplemental Disclosures to Joint Proxy Statement/Prospectus
The following information supplements the Joint Proxy Statement/Prospectus, and should be read in conjunction with the Joint Proxy Statement/Prospectus, which
is available at the SEC’s website, www.sec.gov, and which should be read in its entirety, including the annexes thereto. The information contained in this supplement is incorporated by reference into the Joint Proxy Statement/Prospectus. All
page references and paragraph headings in the information below are references to pages and headings in the Joint Proxy Statement/Prospectus, and the terms used below have the meanings set forth in the Joint Proxy Statement/Prospectus. The
supplemental disclosures are identified below by bold, underlined text. Stricken-through text shows text being deleted from a referenced disclosure in the Joint Proxy Statement/Prospectus.
SUPPLEMENTAL DISCLOSURES TO PROXY STATEMENT