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v3.25.3

Segment information (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information [Line Items] |  |  |  |
Net premiums written | $ 14,866 | $ 13,829 | $ 41,708 | $ 39,410
Net premiums earned | 14,359 | 13,373 | 39,484 | 37,248
Losses and loss expenses | 6,951 | 7,383 | 20,419 | 19,541
Policy acquisition costs | 2,563 | 2,324 | 7,291 | 6,757
Administrative expenses | 1,138 | 1,094 | 3,343 | 3,258
Other (income) expense | (43) | (325) | (781) | (626)
Amortization of purchased intangibles | 75 | 81 | 224 | 241
Segment Income (loss) | 4,218 | 3,272 | 9,957 | 9,462
Net realized gains (losses) | 283 | 198 | 327 | 201
Market risk benefits gains (losses) | (142) | (230) | (251) | (238)
Interest Income (Expense), Net | 197 | 192 | 559 | 552
Integration expenses | 1 | 7 | 3 | 21
Segment Reporting, Other Segment Item, Amount | 48 | (19) | 48 | (100)
Income before income tax | 3,894 | 2,994 | 9,274 | 8,336
North America Commercial P&C Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums written | 5,663 | 5,500 | 16,173 | 15,690
Net premiums earned | 5,080 | 5,110 | 15,245 | 14,890
Losses and loss expenses | 3,083 | 3,391 | 9,372 | 9,640
Segment Liability for Future Policy Benefits, Period Expense (Income) | 0 | 0 | 0 | 0
Policy acquisition costs | 708 | 689 | 2,132 | 2,037
Administrative expenses | 348 | 338 | 1,049 | 993
Underwriting Income (Loss) | 941 | 692 | 2,692 | 2,220
Segment Net Investment Income | 978 | 931 | 2,845 | 2,620
Other (income) expense | 10 | 6 | 26 | 28
Amortization of purchased intangibles | 1 | 2 | 4 | 2
Segment Income (loss) | 1,908 | 1,615 | 5,507 | 4,810
North American Personal P&C Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums written | 1,814 | 1,679 | 5,304 | 4,911
Net premiums earned | 1,741 | 1,577 | 4,996 | 4,560
Losses and loss expenses | 713 | 879 | 3,628 | 2,654
Segment Liability for Future Policy Benefits, Period Expense (Income) | 0 | 0 | 0 | 0
Policy acquisition costs | 339 | 315 | 1,001 | 914
Administrative expenses | 82 | 88 | 251 | 262
Underwriting Income (Loss) | 607 | 295 | 116 | 730
Segment Net Investment Income | 123 | 112 | 361 | 322
Other (income) expense | 1 | 1 | 2 | 0
Amortization of purchased intangibles | 2 | 3 | 6 | 7
Segment Income (loss) | 727 | 403 | 469 | 1,045
North America Agricultural Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums written | 1,458 | 1,379 | 2,467 | 2,386
Net premiums earned | 1,495 | 1,419 | 2,258 | 2,173
Losses and loss expenses | 1,224 | 1,193 | 1,799 | 1,785
Segment Liability for Future Policy Benefits, Period Expense (Income) | 0 | 0 | 0 | 0
Policy acquisition costs | 86 | 88 | 151 | 154
Administrative expenses | 5 | 2 | 9 | 7
Underwriting Income (Loss) | 180 | 136 | 299 | 227
Segment Net Investment Income | 20 | 20 | 63 | 62
Other (income) expense | 0 | 1 | 1 | 1
Amortization of purchased intangibles | 6 | 5 | 18 | 18
Segment Income (loss) | 194 | 150 | 343 | 270
Overseas General Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums written | 3,695 | 3,367 | 11,218 | 10,536
Net premiums earned | 3,803 | 3,421 | 10,554 | 9,966
Losses and loss expenses | 1,707 | 1,631 | 4,893 | 4,728
Segment Liability for Future Policy Benefits, Period Expense (Income) | 119 | 120 | 361 | 312
Policy acquisition costs | 975 | 852 | 2,725 | 2,517
Administrative expenses | 368 | 340 | 1,067 | 1,019
Underwriting Income (Loss) | 634 | 478 | 1,508 | 1,390
Segment Net Investment Income | 288 | 286 | 847 | 836
Other (income) expense | 8 | 5 | 19 | 14
Amortization of purchased intangibles | 20 | 21 | 58 | 61
Segment Income (loss) | 894 | 738 | 2,278 | 2,151
Global Reinsurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums written | 304 | 352 | 1,092 | 1,122
Net premiums earned | 315 | 316 | 1,021 | 950
Losses and loss expenses | 139 | 200 | 513 | 492
Segment Liability for Future Policy Benefits, Period Expense (Income) | 0 | 0 | 0 | 0
Policy acquisition costs | 96 | 89 | 294 | 250
Administrative expenses | 9 | 9 | 29 | 29
Underwriting Income (Loss) | 71 | 18 | 185 | 179
Segment Net Investment Income | 100 | 64 | 255 | 179
Other (income) expense | 0 | 0 | 0 | 0
Amortization of purchased intangibles | 0 | 0 | 0 | 0
Segment Income (loss) | 171 | 82 | 440 | 358
Life Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums written | 1,932 | 1,552 | 5,454 | 4,765
Net premiums earned | 1,925 | 1,530 | 5,410 | 4,709
Losses and loss expenses | 31 | 32 | 77 | 86
Segment Liability for Future Policy Benefits, Period Expense (Income) | 1,303 | 989 | 3,715 | 3,090
Policy acquisition costs | 359 | 291 | 988 | 885
Administrative expenses | 213 | 213 | 614 | 638
Segment Net Investment Income | 284 | 250 | 829 | 738
Other (income) expense | (31) | (39) | (103) | (111)
Amortization of purchased intangibles | 10 | 10 | 28 | 31
Segment Income (loss) | 324 | 284 | 920 | 828
Segment Corporate and Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Underwriting Income (Loss) | (174) | (162) | (469) | (471)
Segment Net Investment Income | (18) | (28) | (74) | (86)
Other (income) expense | 87 | (202) | (408) | (263)
Amortization of purchased intangibles | $ 36 | $ 40 | $ 110 | $ 122

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