Corning Incorporated
MX ˙ BMV ˙ US2193501051
SecurityMX:GLW / Corning Incorporated
InstitutionRock Point Advisors, LLC
Latest Disclosed Ownership35,962 shares
Latest Disclosed Value $ 4,889,753
Rock Point Advisors, LLC reports 49.36% decrease in ownership of GLW / Corning Incorporated

On May 14, 2026 - Rock Point Advisors, LLC filed a 13F-HR form disclosing ownership of 35,962 shares of Corning Incorporated (MX:GLW) valued at $4,889,753 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 4, 2026 disclosing 71,016 shares of Corning Incorporated. This represents a change in shares of -49.36% during the quarter.

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)
2026-05-14 2026-03-31 13F Corning COM 219350105 35,962 -35,054 -49.36 4,890 -21.37 1.3230
2026-02-04 2025-12-31 13F Corning COM 219350105 71,016 -2,169 -2.96 6,218 3.58 1.5566
2025-11-12 2025-09-30 13F Corning COM 219350105 73,185 -47,675 -39.45 6,003 -5.55 1.5909
2025-08-14 2025-06-30 13F Corning COM 219350105 120,860 -825 -0.68 6,356 14.11 1.7930
2025-04-30 2025-03-31 13F Corning COM 219350105 121,685 75 0.06 5,571 -3.60 1.7183
2025-02-13 2024-12-31 13F Corning COM 219350105 121,610 -11,300 -8.50 5,779 -3.70 1.6846
2024-11-13 2024-09-30 13F Corning COM 219350105 132,910 -3,073 -2.26 6,001 13.59 1.6384
2024-08-08 2024-06-30 13F Corning COM 219350105 135,983 -35,637 -20.77 5,283 -6.61 1.5842
2024-05-10 2024-03-31 13F Corning COM 219350105 171,620 1,302 0.76 5,657 9.06 1.6802
2024-02-08 2023-12-31 13F Corning COM 219350105 170,318 9,743 6.07 5,186 6.01 1.5728
2023-11-09 2023-09-30 13F Corning COM 219350105 160,575 4,715 3.03 4,893 -10.42 1.6933
2023-08-10 2023-06-30 13F Corning COM 219350105 155,860 29,246 23.10 5,461 136,425.00 1.7933
2023-05-10 2023-03-31 13F Corning COM 219350105 126,614 -2,735 -2.11 4 0.00 1.5182
2023-02-09 2022-12-31 13F Corning COM 219350105 129,349 -583 -0.45 4 -99.89 1.4299
2022-11-10 2022-09-30 13F Corning COM 219350105 129,932 28,872 28.57 3,771 18.44 1.4017
2022-08-10 2022-06-30 13F Corning COM 219350105 101,060 101,060 3,184 1.0874
2017-05-11 2017-03-31 13F Corning COM 219350105 0 -10,825 -100.00 0 -100.00
2017-02-08 2016-12-31 13F Corning COM 219350105 10,825 -229,818 -95.50 263 -95.38 0.1353
2016-11-02 2016-09-30 13F Corning COM 219350105 240,643 -26,640 -9.97 5,691 3.96 2.9734
2016-07-28 2016-06-30 13F Corning COM 219350105 267,283 -58,620 -17.99 5,474 -19.59 2.9317
2016-04-22 2016-03-31 13F Corning COM 219350105 325,903 -258 -0.08 6,808 14.19 3.6346
2016-02-11 2015-12-31 13F Corning COM 219350105 326,161 1,070 0.33 5,962 7.11 3.1029
2015-11-12 2015-09-30 13F Corning COM 219350105 325,091 213,520 191.38 5,566 152.89 3.0511
2015-08-13 2015-06-30 13F Corning COM 219350105 111,571 -495 -0.44 2,201 -13.41 1.1251
2015-05-14 2015-03-31 13F Corning COM 219350105 112,066 -177,059 -61.24 2,542 -61.66 1.2735
2015-02-12 2014-12-31 13F Corning COM 219350105 289,125 2,695 0.94 6,630 19.68 3.0590
2014-11-12 2014-09-30 13F Corning COM 219350105 286,430 -16,895 -5.57 5,540 -16.79 2.6751
2014-08-07 2014-06-30 13F Corning COM 219350105 303,325 -150,235 -33.12 6,658 -29.49 2.9076
2014-05-13 2014-03-31 13F Corning COM 219350105 453,560 -32,000 -6.59 9,443 9.13 4.1813
2014-02-14 2013-12-31 13F Corning COM 219350105 485,560 4,375 0.91 8,653 23.26 3.7954
2013-11-15 2013-09-30 13F Corning COM 219350105 481,185 -1,770 -0.37 7,020 2.15 3.2675
2013-08-14 2013-06-30 13F Corning COM 219350105 482,955 482,955 6,872 3.4943
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.