1,152 material Form 8-K filings that 918 companies we cover made with the SEC in October 2025, each read and summarized by AI: what happened, the key figures, whether it reads positive or negative for shareholders, and how big a deal it is (impact 1-5). All of them were written later, when past filings were added: a selection, not every 8-K of the month (see the note below).
Mark C. Birk informed Ameren that he will retire as Chairman and President of Union Electric Company (Ameren Missouri), effective October 2, 2025, and from his other subsidiary roles. Senior Executive Vice President and CFO Michael L. Moehn was elected Interim Chairman and President of Ameren Missouri, a role he previously held from 2014 to 2019. The filing does not describe a permanent successor or any financial effect.
Mark C. Birk to retire as Chairman and President of Ameren Missouri, effective October 2, 2025
Michael L. Moehn, Ameren's CFO since 2019, named Interim Chairman and President of Ameren Missouri
Moehn previously served as Chairman and President of Ameren Missouri from 2014 to 2019
Occidental Petroleum's subsidiaries agreed on October 1, 2025 to sell all equity in Occidental Chemical Corporation, which holds its chemical business OxyChem, to Berkshire Hathaway in an all-cash deal. The filing says the price is $9.7 billion, subject to customary cash, debt and working capital adjustments, and the sale is subject to regulatory approvals and other closing conditions.
Purchase price is $9.7 billion in cash, subject to customary adjustments for cash, indebtedness and working capital.
Closing is subject to the Hart-Scott-Rodino waiting period and other required regulatory consents.
Either party may terminate if closing has not occurred by March 30, 2026, with a 90-day automatic extension if regulatory conditions are unmet.
Occidental will guarantee the indemnification obligations of OCH and ERH under the agreement, and ERH retains environmental liabilities for OxyChem's legacy sites.
DENTSPLY SIRONA said its Executive Vice President, Corporate Development, General Counsel and Secretary, Richard C. Rosenzweig, will leave that role by mutual agreement effective October 3, 2025. He will serve as Special Legal Advisor through March 4, 2026 under a transition agreement that sets severance and consulting terms. The change is an executive transition with defined payments rather than a change in financial results.
Rosenzweig's general counsel and corporate development roles end October 3, 2025; he becomes Special Legal Advisor through March 4, 2026 or earlier termination.
Transition agreement, dated October 2, 2025, provides a $30,000 monthly fixed fee for his Special Legal Advisor services, paid in full if terminated before March 4, 2026 for reasons other than Cause.
After the Separation Date, the company will engage him as an independent contractor consultant for one year at $20,000 per month.
TransDigm Group completed a CEO transition on September 30, 2025, when Michael J. Lisman succeeded Kevin M. Stein as president and chief executive officer. Stein remains on the board and has a consulting agreement to advise the company for up to 24 months at $25,000 per month, with some of his stock options continuing to vest and a portion to be forfeited.
Michael J. Lisman succeeded Kevin M. Stein as President and CEO on September 30, 2025.
Stein, who served nearly 11 years, remains a member of the Board of Directors.
Stein's consulting agreement, dated October 1, 2025, runs for up to 24 months at $25,000 per month.
Stein agreed to forfeit a certain portion of his outstanding stock options granted during his CEO tenure.
Nicolas Kuan Liang Lin resigned as Chief Financial Officer and as a director of Origin Investment Corp I, effective September 29, 2025, and the filing says the resignation was not due to any disagreement with the company. CEO Yung-Hsi ("Edward") Chang will serve as interim CFO until a permanent CFO is identified, so shareholders should watch for that appointment.
Nicolas Kuan Liang Lin resigned as CFO and board member effective September 29, 2025
Filing states the resignation was not due to any disagreement on operations, policies or practices
CEO Yung-Hsi ("Edward") Chang will serve as interim CFO until a permanent CFO is named
American Axle & Manufacturing's subsidiary issued $850 million of 6.375% senior secured notes due 2032 and $1.25 billion of 7.750% senior unsecured notes due 2033 on October 3, 2025, to fund the cash consideration for its pending combination with Dowlais Group plc and related costs. The filing names American Axle & Manufacturing Holdings, Inc. (NYSE: AXL), not Dauch Corp (DCH) as listed in the request, and the notes add $2.1 billion of debt before the combination closes.
Notes issued October 3, 2025: $850 million 6.375% secured due October 15, 2032 and $1.25 billion 7.750% unsecured due October 15, 2033.
Proceeds, with credit facility borrowings and cash on hand, are earmarked for the Dowlais cash consideration, repaying Dowlais credit facilities, and redeeming $500 million of 6.50% notes due 2027 and $150 million of 6.875% notes due 2028.
$600 million of unsecured notes and the secured notes are held in escrow; if escrow release conditions are not met by June 29, 2026, they must be redeemed at par plus accrued interest.
Bridge loans of $843 million (first lien) and $500 million (second lien) were terminated effective October 3, 2025.
XBiotech entered into an Executive Employment Agreement with CEO and President John Simard, effective October 1, 2025, replacing his prior employment agreements. The agreement sets a $1,250,000 base salary, an annual base bonus of $4,530,442, and severance of three years of salary and bonus if he retires, leaves due to disability, or is terminated without cause.
Agreement signed October 2, 2025, effective October 1, 2025, superseding all prior employment agreements with Mr. Simard
Base salary of $1,250,000 maintained; annual base bonus of $4,530,442, based on the average annual bonus paid over the past five years and determined each year by the Compensation Committee
Severance of three full calendar years of base salary and base bonus on retirement, disability, or termination without cause, paid in cash within 14 days after the release takes effect
If Mr. Simard retires, he will consult for the company for at least 18 months and continue receiving base salary during that period
Proto Labs said its chief technology officer, Oleg Ryaboy, will leave the company effective November 2, 2025, and that Marc Kermisch will take over as Chief Technology & AI Officer effective October 13, 2025. Ryaboy will receive severance benefits under the company's standard executive severance agreement, and the filing does not state a dollar amount. The change is a senior executive transition with no financial results or guidance included.
Oleg Ryaboy, Chief Technology Officer, departs effective November 2, 2025 and is no longer an executive officer as of October 3, 2025
Marc Kermisch appointed Chief Technology & AI Officer effective October 13, 2025
Kermisch previously served as CTO at Emergent Software and as Global Chief Digital and Information Officer at Case New Holland
Ryaboy's severance follows Section 5(A) of the executive severance agreement filed June 6, 2022
Briefs are written by AI from the filing text and can contain mistakes — open the filing before acting on anything. Impact (1-5) and tone are the AI's reading of the filing for shareholders, not a price forecast. Not investment advice.
Briefs marked “Written later” were written in November 2026 for filings that were by then more than three weeks old, so months before mid-October 2026 hold a selection: every material 8-K of the past year for the 100 largest companies we cover and the last 15 important 8-Ks of every other one. Briefs the number check holds back are not shown or counted. Also: the last 45 days, briefs by company, A–Z and the live SEC filings wire.