Microsoft founder Bill Gates isn’t cashing out of his favorite waste hauler — he’s piling in even harder.

Cascade Investment, Gates’ private investment vehicle, is executing an extended buying streak in Republic Services, Inc. (NYSE:RSG), snapping up roughly 534,000 additional shares on Sept. 1 and Sept. 2 worth an estimated $119.1 million, according to a new SEC Form 4 filing

The new filing pushes Cascade’s total spend on Republic Services stock since Aug. 25 to roughly $424.8 million across 25 separate open-market purchases, spanning 1.92 million shares, at prices ranging from about $220 to $224 a share.

Because Cascade already owns more than 10% of Republic Services, it is required to disclose its trades within days rather than waiting for a quarterly 13F, giving an unusually granular look at how aggressively Gates has been buying.

A day-by-day breakdown of the buying spree:

DateSharesEst. Value
Aug. 25269,477$59.8 million
Aug. 26275,500$61.0 million
Aug. 27284,600$62.5 million
Aug. 28251,400$55.6 million
Aug. 31301,000$66.8 million
Sept. 1204,800$45.6 million
Sept. 2329,200$73.5 million

Trash Pick-Up

Gates has held a position in Republic Services since 2008, making it one of Cascade’s longest-running concentrated holdings outside of his stake in Berkshire Hathaway.

After the latest round of buying, Cascade now holds an estimated 115 million shares of the company — a stake that underscores just how central the trash and recycling giant has become to Gates’s personal portfolio.

Republic Services is the second-largest waste and recycling operator in the U.S., behind only Waste Management, Inc. (NYSE:WM), and has long been viewed by investors as a defensive, cash-generative business with pricing power and steady demand regardless of economic conditions — the kind of “boring but reliable” profile that fits Gates’s long-horizon investing style.

The size and cadence of the buying — five-figure share blocks on nearly every trading day for more than a week — signals conviction rather than a one-off rebalancing move.

With Cascade required to report further purchases in near real time, traders can expect more Form 4 filings if the buying continues.

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