1. Mueller Industries Inc. (NYSE:MLI)
Position Weight / Position Value: 2.1% / $214.4 Million
Mueller Industries Inc. (NYSE:MLI) is the largest holding in GAMCO Investors’ 13F portfolio, accounting for approximately 2.06% of total holdings. That said, it is also the stock that saw the biggest change in Q4 2025 among the 12 largest holdings. GAMCO reduced the position by around 15% to 1.87 million shares, down from 2.19 million in Q3 2025.
GAMCO Investors started building a position around the end of 2009 with 584,000 shares at an average price of $6.16. That position rose to 8.5 million shares by 2018/19 and has since trended downward.
As of March 10, 2026, GAMCO owns approximately 1.68% of Mueller Industries Inc.’s (NYSE: MLI) outstanding shares and is thus the tenth-largest institutional holder.
The stock’s performance has been strong, with over 400% returns in the last 5 years. Closer to now, the stock returned 45% in 2025 and over 13% since the end of the third quarter of 2025 through March 9, 2026. However, the stock has been lacklustre so far in 2026, with the share price largely flat versus the start of the year.
In its Q3 2025 shareholder commentary, GAMCO highlighted Mueller’s positioning as the only vertically integrated North American manufacturer of copper tube and fittings, brass rod, and forgings.
While there have been a number of insider transactions in recent months, one from Mueller Industries’ Chairman and CEO, Gregory Christopher, is worth highlighting. Mr. Christopher sold a total of 350,000 shares during October 23-27, 2025: 158,000 direct shares, plus 70,000 shares from a trust where he is the beneficiary, 72,000 shares from a trust where his wife is the beneficiary, and another 50,000 direct shares. Total proceeds from these transactions were about $36.5 million. Despite the sale, the CEO still holds a large position with 1,069,241 direct shares and some position in various trusts.
Separately, MLI increased its quarterly dividend by 40% in mid-February and now expects to pay a quarterly cash dividend of $0.35 per share on March 27, 2026, to stockholders of record as of the close of business on March 13, 2026.
Mueller Industries Inc. (NYSE:MLI) is a global industrial corporation whose holdings are the leading manufacturers and distributors of highly technical and essential products. These products support critical infrastructure and serve a broad range of industries, including plumbing, heating, ventilation, air conditioning, and refrigeration (HVACR), industrial manufacturing, appliance, transportation, medical, military and defense, and electrical.
While we acknowledge the potential of Mueller Industries Inc. (NYSE:MLI) to grow, our conviction lies in the belief that some AI stocks hold greater promise for delivering higher returns and have limited downside risk. If you are looking for an AI stock that is more promising than MLI and that has 100x upside potential, check out our report about this cheapest AI stock.
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