SCHEDULE: Wellington Management Boosts Clean Harbors Stake to 9.7%

Wellington Management Group LLP and its affiliates reported beneficial ownership of 9.7% of Clean Harbors, Inc. common stock as of December 31, 2025.

Summary

• Wellington Management Group LLP, along with its affiliates Wellington Group Holdings LLP and Wellington Investment Advisors Holdings LLP, collectively reported beneficial ownership of 5,182,538 shares of Clean Harbors, Inc. common stock.
• This ownership represents 9.7% of the class of securities.
• Wellington Management Company LLP, an investment adviser within the group, reported beneficial ownership of 5,182,538 shares, representing 7.9% of the class.
• The shares are held in the ordinary course of business and were not acquired for the purpose of changing or influencing control of Clean Harbors, Inc.
• The filing is an Amendment No. 15 to a Schedule 13G, indicating a long-standing reporting relationship by Wellington Management regarding Clean Harbors.

Sentiment

Score: 7

Explanation: StockSavvy.ai views this as a moderately positive signal, as a significant institutional stake by a reputable firm like Wellington Management often indicates a belief in the company's value and future performance, without suggesting any immediate operational changes.

Positives

• Significant institutional investment by Wellington Management Group LLP and its affiliates, holding 9.7% of Clean Harbors, Inc. common stock, signals confidence in the company.
• The investment is stated to be in the ordinary course of business, suggesting a long-term investment strategy rather than an activist stance.

Future Outlook

NA

Industry Context

StockSavvy.ai notes that a substantial stake by a major institutional investor like Wellington Management can signal confidence in the long-term prospects of Clean Harbors, a leader in environmental and industrial services, potentially influencing other institutional investors.

Stakeholder Impact

• Shareholders: May view the significant institutional ownership as a vote of confidence, potentially leading to increased investor interest and stability.
• Company Management: A large institutional holder can provide oversight and potentially influence strategic decisions, though this filing states no intent to influence control.

Key Dates

Recommendation

The filing indicates a significant, but not activist, stake by a major institutional investor. This suggests a long-term investment perspective and confidence in Clean Harbors. However, it does not provide new operational or financial data to warrant a 'buy' or 'sell' recommendation, rather it reinforces a 'hold' for existing investors and a neutral stance for potential new investors awaiting further fundamental news.

Keywords

Clean Harbors, Wellington Management, Beneficial Ownership, Schedule 13G, Institutional Investor, Common Stock, Environmental Services