The Hanover Insurance Group, Inc.
US ˙ NYSE ˙ US4108671052

SecurityTHG / The Hanover Insurance Group, Inc.
InstitutionBoston Partners
Latest Disclosed Ownership14,034 shares
Latest Disclosed Value $ 2,432,790
Boston Partners reports 5.34% increase in ownership of THG / The Hanover Insurance Group, Inc.

On May 11, 2026 - Boston Partners filed a 13F-HR form disclosing ownership of 14,034 shares of The Hanover Insurance Group, Inc. (US:THG) valued at $2,432,794 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 13,322 shares of The Hanover Insurance Group, Inc.. This represents a change in shares of 5.34% during the quarter. The current value of the position is $2,615,236 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 HANOVER INS GROUP COM 410867105 14,034 712 5.34 2,433 -0.08 0.0011
2026-02-13 2025-12-31 13F HANOVER INS GROUP COM 410867105 13,322 -13,078 -49.54 2,435 -49.24 0.0025
2025-11-13 2025-09-30 13F HANOVER INS GROUP COM 410867105 26,400 -8,482 -24.32 4,795 -19.07 0.0049
2025-08-12 2025-06-30 13F/A-1 HANOVER INS GROUP COM 410867105 34,882 20,432 141.40 5,925 135.77 0.0066
2025-08-07 2025-06-30 13F HANOVER INS GROUP COM 410867105 15,161 711 2,575 0.0012
2025-05-13 2025-03-31 13F HANOVER INS GROUP COM 410867105 14,450 445 3.18 2,514 16.02 0.0030
2025-02-11 2024-12-31 13F HANOVER INS GROUP COM 410867105 14,005 -3,501 -20.00 2,166 -16.44 0.0026
2024-11-12 2024-09-30 13F HANOVER INS GROUP COM 410867105 17,506 26 0.15 2,593 18.25 0.0031
2024-08-14 2024-06-30 13F HANOVER INS GROUP COM 410867105 17,480 4,686 36.63 2,193 26.05 0.0027
2024-05-28 2024-03-31 13F/A-1 HANOVER INS GROUP COM 410867105 12,794 6,753 111.79 1,739 137.24 0.0021
2024-05-13 2024-03-31 13F HANOVER INS GROUP COM 410867105 12,794 6,753 1,739 0.0009
2024-02-07 2023-12-31 13F HANOVER INS GROUP COM 410867105 6,041 -1,692 -21.88 733 -14.57 0.0010
2023-11-08 2023-09-30 13F HANOVER INS GROUP COM 410867105 7,733 -136,006 -94.62 858 -94.71 0.0012
2023-08-10 2023-06-30 13F HANOVER INS GROUP COM 410867105 143,739 -16,784 -10.46 16,227 -20.14 0.0218
2023-05-09 2023-03-31 13F HANOVER INS GROUP COM 410867105 160,523 -91,932 -36.42 20,319 -40.22 0.0279
2023-02-08 2022-12-31 13F HANOVER INS GROUP COM 410867105 252,455 -96,338 -27.62 33,992 -25.72 0.0460
2022-11-09 2022-09-30 13F HANOVER INS GROUP COM 410867105 348,793 -6,392 -1.80 45,761 -10.48 0.0670
2022-08-10 2022-06-30 13F HANOVER INS GROUP COM 410867105 355,185 9,168 2.65 51,118 -1.41 0.0714
2022-05-10 2022-03-31 13F HANOVER INS GROUP COM 410867105 346,017 7,998 2.37 51,850 16.59 0.0628
2022-02-04 2021-12-31 13F HANOVER INS GROUP COM 410867105 338,019 -2,061 -0.61 44,472 -0.06 0.0536
2021-11-05 2021-09-30 13F HANOVER INS GROUP COM 410867105 340,080 -2,782 -0.81 44,500 -4.55 0.0564
2021-08-12 2021-06-30 13F HANOVER INS GROUP COM 410867105 342,862 3,773 1.11 46,619 5.61 0.0595
2021-05-10 2021-03-31 13F HANOVER INS GROUP COM 410867105 339,089 -3,791 -1.11 44,142 10.11 0.0592
2021-02-10 2020-12-31 13F/A-1 HANOVER INS GROUP COM 410867105 342,880 -21,591 -5.92 40,089 18.04 0.0623
2021-02-04 2020-12-31 13F HANOVER INS GROUP COM 410867105 342,880 -21,591 40,089 24,051.0172
2020-11-13 2020-09-30 13F/A-1 HANOVER INS GROUP COM 410867105 364,471 -24,093 -6.20 33,961 -13.51 0.0618
2020-11-09 2020-09-30 13F HANOVER INS GROUP COM 410867105 388,564 0 39,265 28,825.1873
2020-08-12 2020-06-30 13F HANOVER INS GROUP COM 410867105 388,564 108,729 38.85 39,265 55.30 0.0721
2020-05-13 2020-03-31 13F HANOVER INS GROUP COM 410867105 279,835 -10,213 -3.52 25,284 -36.21 0.0502
2020-02-06 2019-12-31 13F/A-1 HANOVER INS GROUP COM 410867105 290,048 32,872 12.78 39,637 14.06 0.0524
2020-02-05 2019-12-31 13F HANOVER INS GROUP COM 410867105 290,048 32,872 39,637 22,285.0791
2019-11-20 2019-09-30 13F/A-1 HANOVER INS GROUP COM 410867105 257,176 -11,804 -4.39 34,752 0.61 0.0471
2019-11-08 2019-09-30 13F HANOVER INS GROUP COM 410867105 269,165 185 34,610 0.0458
2019-08-26 2019-06-30 13F/A-1 HANOVER INS GROUP COM 410867105 268,980 -4,787 -1.75 34,543 10.52 0.0453
2019-08-09 2019-06-30 13F HANOVER INS GROUP COM 410867105 268,980 -4,787 34,543
2019-05-13 2019-03-31 13F/A-1 HANOVER INS GROUP COM 410867105 273,767 4,136 1.53 31,256 -0.72 0.0414
2019-05-03 2019-03-31 13F HANOVER INS GROUP COM 410867105 273,767 4,136 31,256
2019-02-07 2018-12-31 13F HANOVER INS GROUP COM 410867105 269,631 -141,126 -34.36 31,484 -37.87 0.0452
2018-11-14 2018-09-30 13F HANOVER INS GROUP COM 410867105 410,757 -5,843 -1.40 50,675 1.74 0.0589
2018-08-03 2018-06-30 13F HANOVER INS GROUP COM 410867105 416,600 -3,578 -0.85 49,809 0.56 0.0597
2018-05-04 2018-03-31 13F HANOVER INS GROUP COM 410867105 420,178 -22,981 -5.19 49,534 3.42 0.0597
2018-02-14 2017-12-31 13F/A-1 HANOVER INS GROUP COM 410867105 443,159 -174,785 -28.28 47,896 -20.04 0.0564
2018-02-01 2017-12-31 13F HANOVER INS GROUP COM 410867105 443,159 -174,785 47,896
2017-11-02 2017-09-30 13F HANOVER INS GROUP COM 410867105 617,944 16,663 2.77 59,898 12.40 0.0740
2017-08-02 2017-06-30 13F HANOVER INS GROUP COM 410867105 601,281 7,014 1.18 53,291 -0.43 0.0678
2017-05-03 2017-03-31 13F HANOVER INS GROUP COM 410867105 594,267 251,620 73.43 53,520 71.62 0.0683
2017-02-06 2016-12-31 13F HANOVER INS GROUP COM 410867105 342,647 -2,238 -0.65 31,185 19.89 0.0410
2016-11-09 2016-09-30 13F HANOVER INS GROUP COM 410867105 344,885 7,664 2.27 26,012 -8.84 0.0364
2016-08-05 2016-06-30 13F HANOVER INS GROUP COM 410867105 337,221 1,296 0.39 28,535 -5.85 0.0412
2016-05-12 2016-03-31 13F HANOVER INS GROUP COM 410867105 335,925 -25,800 -7.13 30,307 3.00 0.0446
2016-02-08 2015-12-31 13F HANOVER INS GROUP COM 410867105 361,725 -24,081 -6.24 29,423 -1.85 0.0421
2015-11-10 2015-09-30 13F HANOVER INS GROUP COM 410867105 385,806 14,767 3.98 29,977 9.13 0.0457
2015-08-10 2015-06-30 13F HANOVER INS GROUP COM 410867105 371,039 36,946 11.06 27,468 13.27 0.0395
2015-05-05 2015-03-31 13F HANOVER INS GROUP COM 410867105 334,093 254 0.08 24,249 1.84 0.0361
2015-02-09 2014-12-31 13F HANOVER INS GROUP COM 410867105 333,839 -3,063 -0.91 23,810 15.06 0.0357
2014-11-12 2014-09-30 13F HANOVER INS GROUP COM 410867105 336,902 9,369 2.86 20,693 0.05 0.0336
2014-08-08 2014-06-30 13F HANOVER INS GROUP COM 410867105 327,533 -16,560 -4.81 20,683 -2.17 0.0346
2014-05-07 2014-03-31 13F HANOVER INS GROUP COM 410867105 344,093 -23,011 -6.27 21,141 -3.56 0.0386
2014-02-06 2013-12-31 13F HANOVER INS GROUP COM 410867105 367,104 -2,280 -0.62 21,921 7.28 0.0449
2013-11-12 2013-09-30 13F HANOVER INS GROUP COM 410867105 369,384 -7,660 -2.03 20,434 10.77 0.0493
2013-08-01 2013-06-30 13F HANOVER INS GROUP COM 410867105 377,044 377,044 18,448 0.0508
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.