Advanced Drainage Systems (WMS) Soared as Multiple Tailwinds Align

Brown Brothers Harriman, an investment management company, released its Q3 2025 investor letter for the BBH Select Series – Mid Cap Fund. A copy of the same can be downloaded here. In the quarter, the fund decreased by -0.9% on a total return basis compared to the Russell Midcap Index’s 5.3% return. The Fund has decreased by a total return of -1.8%, YTD, compared to 10.4% for the Index. The third quarter experienced a boost in the low-quality rally that started late last year and gained momentum throughout 2025. For more information on the fund’s best picks in 2025, please check its top five holdings.

In its third-quarter 2025 investor letter, BBH Select Series – Mid Cap Fund highlighted stocks such as Advanced Drainage Systems, Inc. (NYSE:WMS). Advanced Drainage Systems, Inc. (NYSE:WMS) is a manufacturer and marketer of thermoplastic corrugated pipes and related water management products. The one-month return of Advanced Drainage Systems, Inc. (NYSE:WMS) was -2.42%, and its shares gained 13.05% of their value over the last 52 weeks. On December 09, 2025, Advanced Drainage Systems, Inc. (NYSE:WMS) stock closed at $144.80 per share, with a market capitalization of $11.26 billion.

BBH Select Series – Mid Cap Fund stated the following regarding Advanced Drainage Systems, Inc. (NYSE:WMS) in its third quarter 2025 investor letter:

“For the quarter, the Fund’s largest positive contributors were Arista Networks Inc. (Arista) and Advanced Drainage Systems, Inc. (NYSE:WMS).

Advanced Drainage Systems, Inc. (NYSE:WMS) is not on our list of 30 Most Popular Stocks Among Hedge Funds. As per our database, 36 hedge fund portfolios held Advanced Drainage Systems, Inc. (NYSE:WMS) at the end of the third quarter, the same as in the previous quarter. In the second quarter of fiscal 2026, Advanced Drainage Systems, Inc.’s (NYSE:WMS) revenue increased 9% to $850 million. While we acknowledge the potential of Advanced Drainage Systems, Inc. (NYSE:WMS) as an investment, we believe certain AI stocks offer greater upside potential and carry less downside risk. If you’re looking for an extremely undervalued AI stock that also stands to benefit significantly from Trump-era tariffs and the onshoring trend, see our free report on the best short-term AI stock.

In another article, we covered Advanced Drainage Systems, Inc. (NYSE:WMS) and shared Madison Small Cap Fund’s views on the company. In addition, please check out our hedge fund investor letters Q3 2025 page for more investor letters from hedge funds and other leading investors.

READ NEXT: The Best and Worst Dow Stocks for the Next 12 Months and 10 Unstoppable Stocks That Could Double Your Money.

Disclosure: None. This article is originally published at Insider Monkey.