Institutional Manager · CIK 0001496228
SRB CORP
BOSTON, MA · File #028-15030
Latest AUM
$1.82B
Positions
44
Top-10 Concentration
48.3%
Filings
9
Portfolio Value Over Time
2024-03
2024-06
2024-09
2024-12
2025-03
2025-06
2025-09
2025-12
Biggest QoQ Changes
Ranked by conviction flow (share change × current price) so mark-to-market moves don't dominate. Price effect column shows how much of the $ change was just the stock moving.
| Action | Issuer | Ticker / CUSIP | Δ Shares | Flow ($) | Price Effect |
|---|---|---|---|---|---|
| ADD | SEL SECTOR:TECH SPDR | 81369Y803 | +324,251 | +$46.7M | -$37.5M |
| ADD | SEL SECTOR:MAT SS SPDR | 81369Y100 | +462,678 | +$21.0M | -$20.5M |
| ADD | SEL SCTR:C D SS SPDR IN | 81369Y407 | +55,380 | +$6.6M | -$6.7M |
| ADD | COMCAST CL A ORD | CCZ | +34,801 | +$1.0M | -$299,346 |
| REDUCE | ALPHABET CL A ORD | GOOG | 0 | $0 | +$8.9M |
| REDUCE | AMAZON COM ORD | AMZN | 0 | $0 | +$2.8M |
| REDUCE | CVS HEALTH ORD | CVS | 0 | $0 | +$516,334 |
| REDUCE | GE AEROSPACE ORD | 369604301 | 0 | $0 | +$1.4M |
| REDUCE | INTEL ORD | INTC | 0 | $0 | +$4.6M |
| REDUCE | MERCK & CO ORD | MRK | 0 | $0 | +$5.1M |
Sector Allocation
Filing History
- 13F HOLDINGS REPORTQ/E Dec 202544 pos · $1.82B
- 13F HOLDINGS REPORTQ/E Sep 202544 pos · $1.74B
- 13F HOLDINGS REPORTQ/E Jun 202544 pos · $1.67B
- 13F HOLDINGS REPORTQ/E Mar 202543 pos · $1.53B
- 13F HOLDINGS REPORTQ/E Dec 202440 pos · $1.74B
- 13F HOLDINGS REPORTQ/E Sep 202436 pos · $1.78B
- 13F HOLDINGS REPORTQ/E Jun 202438 pos · $1.69B
- 13F HOLDINGS REPORTQ/E Mar 2024149 pos · $1.81B
- 13F HOLDINGS REPORTQ/E Dec 2023188 pos · $1.65B
Top 20 Holdings — Dec 2025
| # | Issuer | Ticker | Shares | Value | % of Portfolio |
|---|---|---|---|---|---|
| 1 | MICROSOFT ORD | MSFT | 354,509 | $171.4M | 9.41% |
| 2 | MICROSOFT ORD | MSFT | 338,414 | $163.7M | 8.98% |
| 3 | RENAISSANCERE ORD | RNR-PG | 334,374 | $94.0M | 5.16% |
| 4 | SEL SECTOR:TECH SPDR | 81369Y803 | 596,326 | $85.9M | 4.71% |
| 5 | SAFETY INSURANCE GROUP ORD | 78648T100 | 1,026,751 | $80.0M | 4.39% |
| 6 | SAFETY INSURANCE GROUP ORD | 78648T100 | 815,533 | $63.5M | 3.49% |
| 7 | GE AEROSPACE ORD | 369604301 | 190,754 | $58.8M | 3.23% |
| 8 | AMAZON COM ORD | AMZN | 245,478 | $56.7M | 3.11% |
| 9 | GE AEROSPACE ORD | 369604301 | 179,141 | $55.2M | 3.03% |
| 10 | SEL SECTOR:HC SS SPDR | 81369Y209 | 332,074 | $51.4M | 2.82% |
| 11 | INTEL ORD | INTC | 1,376,744 | $50.8M | 2.79% |
| 12 | SEL SCTR:COMS SS SPDR | 81369Y852 | 428,427 | $50.4M | 2.77% |
| 13 | AMAZON COM ORD | AMZN | 214,972 | $49.6M | 2.72% |
| 14 | SEL SCTR:COMS SS SPDR | 81369Y852 | 372,347 | $43.8M | 2.41% |
| 15 | WALMART ORD | WMT | 382,452 | $42.6M | 2.34% |
| 16 | SEL SECTOR:MAT SS SPDR | 81369Y100 | 925,356 | $42.0M | 2.30% |
| 17 | ALPHABET CL A ORD | GOOG | 127,117 | $39.8M | 2.18% |
| 18 | WALMART ORD | WMT | 344,598 | $38.4M | 2.11% |
| 19 | WW GRAINGER ORD | 384802104 | 37,380 | $37.7M | 2.07% |
| 20 | SEL SECTOR:TECH SPDR | 81369Y803 | 257,098 | $37.0M | 2.03% |