Constellium Se CSTM Institutional Ownership

Updated Oct 11, 2026

Constellium Se (NYSE:CSTM) had 384 institutional holders reporting a position on Form 13F for the quarter ended June 30, 2026.

• Their combined stake equaled 88.57% of outstanding shares in Q2 2026, down from 92.55% in Q1 2026.
• Total holdings of Constellium Se shares fell 4.51% from Q1 2026, and the number of holders rose 72.97% from Q2 2025.
• Of the 384 holders of CSTM in Q2 2026, 255 added to their positions, 108 reduced their stakes and 21 left their positions unchanged.
• Altogether, institutional holders owned 120.33Mn CSTM shares at the end of Q2 2026, down 5.68Mn from the prior quarter and down 10.38Mn from a year earlier.
• As of June 30, 2026, the biggest holder of Constellium Se was BlackRock, Inc. with 12.8Mn shares, or 9.42% of shares outstanding.
• Among holders that already owned Constellium Se, the biggest buyers in Q2 2026 were Morgan Stanley (+2.99Mn shares), American Century Companies Inc (+2.14Mn shares), Kinetic Partners Management, LP (+1.23Mn shares), Marshall Wace, LLP (+1.08Mn shares) and Acadian Asset Management LLC (+834.64K shares).
• The biggest cuts to CSTM positions during Q2 2026 came from FMR LLC (-4.77Mn shares), Bpifrance SA (-4.19Mn shares), Millennium Management LLC (-1.51Mn shares), D. E. Shaw & Co., Inc. (-1.04Mn shares) and T. Rowe Price Investment Management, Inc. (-980.25K shares).
• Business Quant data shows the 10 biggest positions in Constellium Se as of Q2 2026 were held by BlackRock, Inc. (12.8Mn shares), Bpifrance SA (8.4Mn shares), Morgan Stanley (6.18Mn shares), Vanguard Portfolio Management LLC (4.39Mn shares), American Century Companies Inc (4.22Mn shares), T. Rowe Price Investment Management, Inc. (2.98Mn shares), State Street Corp (2.95Mn shares), Arrowstreet Capital, Limited Partnership (2.84Mn shares), Nuveen, LLC (2.77Mn shares) and Kinetic Partners Management, LP (2.54Mn shares).