Corning Incorporated
MX ˙ BMV ˙ US2193501051
SecurityMX:GLW / Corning Incorporated
InstitutionMarathon Capital Management
Latest Disclosed Ownership105,187 shares
Latest Disclosed Value $ 14,302,253
Marathon Capital Management reports 43.27% decrease in ownership of GLW / Corning Incorporated

On May 14, 2026 - Marathon Capital Management filed a 13F-HR form disclosing ownership of 105,187 shares of Corning Incorporated (MX:GLW) valued at $14,302,253 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 29, 2026 disclosing 185,415 shares of Corning Incorporated. This represents a change in shares of -43.27% 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 105,187 -80,228 -43.27 14,302 -11.90 3.2122
2026-01-29 2025-12-31 13F CORNING COM 219350105 185,415 -8,509 -4.39 16,235 2.06 3.4938
2025-11-14 2025-09-30 13F CORNING COM 219350105 193,924 -15,893 -7.57 15,908 44.16 3.6402
2025-08-14 2025-06-30 13F CORNING COM 219350105 209,817 -4,391 -2.05 11,034 12.52 2.8103
2025-05-15 2025-03-31 13F CORNING COM 219350105 214,208 -21,737 -9.21 9,806 -12.54 2.6118
2025-02-14 2024-12-31 13F CORNING COM 219350105 235,945 3,875 1.67 11,212 7.02 2.8003
2024-11-14 2024-09-30 13F CORNING COM 219350105 232,070 -2,285 -0.98 10,478 15.08 2.5403
2024-08-14 2024-06-30 13F CORNING COM 219350105 234,355 -3,924 -1.65 9,105 15.93 2.3203
2024-05-15 2024-03-31 13F CORNING COM 219350105 238,279 -1,114 -0.47 7,854 7.74 1.8741
2024-02-14 2023-12-31 13F/A-1 CORNING COM 219350105 239,393 -2,975 -1.23 7,290 -1.29 1.8323
2024-02-08 2023-12-31 13F CORNING COM 219350105 239,393 -2,975 7,290 1.8323
2023-11-14 2023-09-30 13F CORNING COM 219350105 242,368 -482 -0.20 7,385 -13.22 1.8584
2023-08-15 2023-06-30 13F/A-1 CORNING COM 219350105 242,850 -2,014 -0.82 8,509 -1.49 2.1005
2023-08-14 2023-06-30 13F CORNING COM 219350105 242,850 -2,014 8,509 2.0613
2023-05-12 2023-03-31 13F CORNING COM 219350105 244,864 -409 -0.17 8,639 10.26 2.1257
2023-02-14 2022-12-31 13F CORNING COM 219350105 245,273 92,932 61.00 7,834 77.20 2.1593
2022-11-14 2022-09-30 13F Corning COM 219350105 152,341 -23 -0.02 4,421 -7.92 1.2630
2022-08-12 2022-06-30 13F Corning COM 219350105 152,364 1,646 1.09 4,801 -13.70 1.5509
2022-05-13 2022-03-31 13F Corning COM 219350105 150,718 4,200 2.87 5,563 1.98 1.5969
2022-02-09 2021-12-31 13F Corning COM 219350105 146,518 -416 -0.28 5,455 1.73 1.2783
2021-11-15 2021-09-30 13F Corning COM 219350105 146,934 -260 -0.18 5,362 -10.93 1.2172
2021-08-16 2021-06-30 13F Corning COM 219350105 147,194 -2,569 -1.72 6,020 -7.61 1.3936
2021-05-14 2021-03-31 13F Corning COM 219350105 149,763 5,607 3.89 6,516 25.57 1.7178
2021-02-08 2020-12-31 13F Corning COM 219350105 144,156 -3,062 -2.08 5,189 8.76 1.5294
2020-11-16 2020-09-30 13F Corning COM 219350105 147,218 -11,378 -7.17 4,771 16.14 1.7367
2020-08-14 2020-06-30 13F Corning COM 219350105 158,596 -785 -0.49 4,108 25.51 1.5779
2020-05-15 2020-03-31 13F Corning COM 219350105 159,381 6,025 3.93 3,273 -26.68 1.5027
2020-02-14 2019-12-31 13F Corning COM 219350105 153,356 37,544 32.42 4,464 35.15 1.5181
2019-11-13 2019-09-30 13F Corning COM 219350105 115,812 28,662 32.89 3,303 14.09 1.3321
2019-07-25 2019-06-30 13F Corning COM 219350105 87,150 -567 -0.65 2,895 -0.28 1.1806
2019-05-15 2019-03-31 13F Corning COM 219350105 87,717 -1,725 -1.93 2,903 7.44 1.2966
2019-02-07 2018-12-31 13F Corning COM 219350105 89,442 -1,333 -1.47 2,702 42.51 1.3412
2016-05-13 2016-03-31 13F Corning EQ 219350105 90,775 4,225 4.88 1,896 19.85 0.9813
2016-02-12 2015-12-31 13F Corning EQ 219350105 86,550 86,550 0.00 1,582 0.8377
2014-10-30 2014-09-30 13F Corning COM 219350105 0 -11,555 -100.00 0 -100.00
2014-08-08 2014-06-30 13F Corning COM 219350105 11,555 0 0.00 254 5.39 0.2043
2014-04-30 2014-03-31 13F Corning COM 219350105 11,555 -1,300 -10.11 241 5.24 0.1811
2014-01-28 2013-12-31 13F Corning COM 219350105 12,855 200 1.58 229 23.78 0.1652
2013-11-04 2013-09-30 13F Corning COM 219350105 12,655 0 0.00 185 2.78 0.1589
2013-07-25 2013-06-30 13F Corning COM 219350105 12,655 12,655 180 0.1536
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.