ADVANCED DRAIN SYS INC DEL
594 institutions still hold ADVANCED DRAIN SYS INC DEL as of Q1 2026. Tracked across SEC 13F-HR filings, with insider and 13D/G activity surfaced alongside.
Institutional ownership of Advanced Drainage Systems (WMS) is effectively a three-firm story: of $136.8 million spread across just 43 holders as of Q2 2026, Swedbank AB, Sweden's largest bank, alone accounts for $64.5 million — 47.1% of all institutional value — after nearly tripling its share count this quarter (+148.9%, a genuine $38.6 million addition, by far the largest flow of any holder in this batch). Add BDF-Gestion ($30.5 million, 22.3%) and Perpetual Ltd ($16.7 million, 12.2%), and just three holders control 82% of the stock's entire institutional ownership. BDF-Gestion is worth a second look: it trimmed its share count by 10.1% (a real $3.4 million sale) yet its position's dollar value still rose $28.7 million, meaning the stock's own price gain this quarter dwarfed the effect of the sale several times over. Perpetual Ltd added the second-largest genuine stake, up 34.4% in shares ($4.3 million). Four new holders — Cannon Advisors, First Bank & Trust, Wedmont Private Capital and New England Research & Management — opened positions this quarter, while Empirical Wealth Management cut its stake in half.
Top holders
Sorted by position value. Source: SEC EDGAR 13F-HR filings.