Gibraltar Industries, Inc.
US ˙ NasdaqGS ˙ US3746891072

SecurityROCK / Gibraltar Industries, Inc.
InstitutionBoston Partners
Latest Disclosed Ownership686,625 shares
Latest Disclosed Value $ 27,285,322
Boston Partners reports 25.67% decrease in ownership of ROCK / Gibraltar Industries, Inc.

On May 11, 2026 - Boston Partners filed a 13F-HR form disclosing ownership of 686,625 shares of Gibraltar Industries, Inc. (US:ROCK) valued at $27,375,739 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 923,711 shares of Gibraltar Industries, Inc.. This represents a change in shares of -25.67% during the quarter. The current value of the position is $25,837,699 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-11 2026-03-31 13F GIBRALTAR INDS COM 374689107 686,625 -237,086 -25.67 27,285 -40.67 0.0122
2026-02-13 2025-12-31 13F GIBRALTAR INDS COM 374689107 923,711 897,935 3,483.61 45,993 2,740.77 0.0476
2025-11-13 2025-09-30 13F GIBRALTAR INDS COM 374689107 25,776 25,776 1,619 0.0017
2023-05-09 2023-03-31 13F GIBRALTAR INDS COM 374689107 0 -14,515 -100.00 0 -100.00
2023-02-08 2022-12-31 13F GIBRALTAR INDS COM 374689107 14,515 337 2.38 666 14.66 0.0009
2022-11-09 2022-09-30 13F GIBRALTAR INDS COM 374689107 14,178 282 2.03 580 7.81 0.0008
2022-08-10 2022-06-30 13F GIBRALTAR INDS COM 374689107 13,896 5,525 66.00 538 49.44 0.0008
2022-05-10 2022-03-31 13F GIBRALTAR INDS COM 374689107 8,371 244 3.00 360 -33.58 0.0004
2022-02-04 2021-12-31 13F GIBRALTAR INDS COM 374689107 8,127 -1,115 -12.06 542 -15.84 0.0007
2021-11-05 2021-09-30 13F GIBRALTAR INDS COM 374689107 9,242 -1,332 -12.60 644 -20.20 0.0008
2021-08-12 2021-06-30 13F GIBRALTAR INDS COM 374689107 10,574 -1,315 -11.06 807 -25.83 0.0010
2021-05-10 2021-03-31 13F GIBRALTAR INDS COM 374689107 11,889 -4,555 -27.70 1,088 -8.03 0.0015
2021-02-10 2020-12-31 13F/A-1 GIBRALTAR INDS COM 374689107 16,444 -8,674 -34.53 1,183 -27.69 0.0018
2021-02-04 2020-12-31 13F GIBRALTAR INDS COM 374689107 16,444 -8,674 1,183 709.7297
2020-11-13 2020-09-30 13F/A-1 GIBRALTAR INDS COM 374689107 25,118 -241 -0.95 1,636 34.43 0.0030
2020-11-09 2020-09-30 13F GIBRALTAR INDS COM 374689107 25,359 0 1,217 893.4230
2020-08-12 2020-06-30 13F GIBRALTAR INDS COM 374689107 25,359 -3,577 -12.36 1,217 -2.01 0.0022
2020-05-13 2020-03-31 13F GIBRALTAR INDS COM 374689107 28,936 -263,266 -90.10 1,242 -77.14 0.0025
2014-02-06 2013-12-31 13F GIBRALTAR INDS COM 374689107 292,202 0 0.00 5,432 30.36 0.0111
2013-11-12 2013-09-30 13F GIBRALTAR INDS COM 374689107 292,202 -96,115 -24.75 4,167 -26.30 0.0100
2013-08-01 2013-06-30 13F GIBRALTAR INDS COM 374689107 388,317 388,317 5,654 0.0156
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.