GIBRALTAR INDUSTRIES INC (ROCK) Institutional Ownership Changes & 13F Activity
GIBRALTAR INDUSTRIES INC (ROCK). Institutional ownership data tracks hedge funds, asset managers, and other institutional investors based on recent SEC Form 13F filings (Q2 2026). This page analyzes institutional buying and selling activity, new holdings, and sold-out positions in the latest reporting period. Notable filers include Simcoe Capital Management, Llc, First Wilshire Securities Management Inc, Palisade Capital Management, Lp, Invesco Ltd., and Frontier Capital Management Co Llc.
| Institution | Type | Change in shares | Change Position % | Shares | Reported stock balance | Portfolio quarter | Filing date |
|---|---|---|---|---|---|---|---|
| Envestnet Asset Management Inc | Buy | +2,979 | +36.9% | 11,054 | $498.52K | Q2 2026 | Sep 23, 2026 |
| State Street Corp | Sell | -116,681 | -8.7% | 1,228,984 | $55.41M | Q2 2026 | Sep 22, 2026 |
| Manufacturers Life Insurance Company, The | Buy | +57 | +0.4% | 13,092 | $590.45K | Q2 2026 | Sep 09, 2026 |
| Parkside Financial Bank & Trust | Sell | -113 | -6.7% | 1,574 | $70.99K | Q2 2026 | Sep 04, 2026 |
| Citadel Advisors Llc | Buy | +72,658 | +61.3% | 191,107 | $8.62M | Q2 2026 | Sep 02, 2026 |
| Corient Private Wealth Llc | Sell | -7,728 | -25.0% | 23,242 | $1.05M | Q2 2026 | Aug 27, 2026 |
| California State Teachers Retirement System | Buy | +5,661 | +20.4% | 33,404 | $1.51M | Q2 2026 | Aug 24, 2026 |
| Assenagon Asset Management S.A. | Sell | -33,462 | -67.4% | 16,197 | $730.49K | Q2 2026 | Aug 21, 2026 |
| Mercer Global Advisors Inc | Buy | +4,732 | — | 4,732 | $213.41K | Q2 2026 | Aug 19, 2026 |
| Fulcrum Asset Management Llp | Buy | +34 | — | 34 | $1.52K | Q2 2026 | Aug 18, 2026 |
| Public Employees Retirement System Of Ohio | Buy | +211 | +25.8% | 1,029 | $46.41K | Q2 2026 | Aug 17, 2026 |
| Simcoe Capital Management, Llc | Buy | +494,365 | — | 494,365 | $22.30M | Q2 2026 | Aug 14, 2026 |
| First Wilshire Securities Management Inc | Sell | -231,150 | -46.2% | 268,773 | $12.12M | Q2 2026 | Aug 14, 2026 |
| Palisade Capital Management, Lp | Sell | -190,444 | -53.1% | 168,431 | $7.60M | Q2 2026 | Aug 14, 2026 |
| Invesco Ltd. | Buy | +144,410 | — | 144,410 | $6.51M | Q2 2026 | Aug 14, 2026 |
| Frontier Capital Management Co Llc | Buy | +142,000 | +20.6% | 830,272 | $37.45M | Q2 2026 | Aug 14, 2026 |
| Balyasny Asset Management L.P. | Buy | +126,627 | +108.4% | 243,403 | $10.98M | Q2 2026 | Aug 14, 2026 |
| Royce & Associates Lp | Buy | +113,824 | +39.4% | 402,365 | $18.15M | Q2 2026 | Aug 14, 2026 |
| Monimus Capital Management, Lp | Buy | +91,939 | — | 91,939 | $4.15M | Q2 2026 | Aug 14, 2026 |
| Ameriprise Financial Inc | Buy | +87,546 | — | 87,546 | $3.95M | Q2 2026 | Aug 14, 2026 |
| Man Group Plc | Buy | +83,282 | — | 83,282 | $3.76M | Q2 2026 | Aug 14, 2026 |
| Squarepoint Ops Llc | Buy | +83,148 | — | 83,148 | $3.75M | Q2 2026 | Aug 14, 2026 |
| Susquehanna International Group, Llp | Buy | +70,441 | +455.3% | 85,913 | $3.87M | Q2 2026 | Aug 14, 2026 |
| Goldman Sachs Group Inc | Sell | -69,597 | -35.7% | 125,116 | $5.64M | Q2 2026 | Aug 14, 2026 |
| Aqr Capital Management Llc | Buy | +63,553 | +66.2% | 159,586 | $7.20M | Q2 2026 | Aug 14, 2026 |
| Mirae Asset Global Etfs Holdings Ltd. | Buy | +63,353 | +8.5% | 805,620 | $36.33M | Q2 2026 | Aug 14, 2026 |
| Millennium Management Llc | Buy | +56,573 | — | 56,573 | $2.55M | Q2 2026 | Aug 14, 2026 |
| Lazard Asset Management Llc | Buy | +47,270 | +384.9% | 59,550 | $2.69M | Q2 2026 | Aug 14, 2026 |
| Alliancebernstein L.P. | Buy | +34,379 | +1.6% | 2,232,832 | $89.02M | Q2 2026 | Aug 14, 2026 |
| Castleknight Management Lp | Sell | -28,000 | -18.6% | 122,500 | $5.52M | Q2 2026 | Aug 14, 2026 |
Frequently asked questions about ROCK activity
Which institutional owners are buying ROCK?
Institutional owners buying ROCK include investors who have either initiated new positions or increased their existing holdings based on recent SEC 13F filings. The activity table above highlights which funds added shares in the latest reporting periods and how their positions changed over time.
What does "buy" mean in ROCK activity?
"Buy" means an investor increased their reported position in ROCK compared to the prior reporting period. This reflects growing exposure to GIBRALTAR INDUSTRIES INC (ROCK) rather than necessarily a brand-new position (though new positions also appear as buys when prior quantity was zero).
Is institutional interest in ROCK increasing?
Institutional interest in ROCK can be assessed by comparing the number of tracked funds adding or increasing positions versus those trimming or exiting across the periods shown. A higher number of additions typically signals increasing participation among large filers, but it should be read alongside position sizes and the full table.
Related ROCK Institutional Insights
- ROCK Overview
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- ROCK Top Institutional Shareholders
- Industrials Sector Institutional Ownership
- Industrials Sector Portfolio Overlap
- Institutional Portfolio Overlap & Shared Holdings
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- ROCK Insider Trading & SEC Form 4 Activity
- ROCK Articles
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