SRB CORP — 13F Holdings & Portfolio
CIK 1496228 · latest 13F-HR filed 2026-08-14
SRB CORP manages $1.86B in 13F-reported U.S. long-equity assets across 46 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are XLK (8.32%), MSFT (6.43%), RNR (5.30%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 0 new positions and exited 0; 14 existing positions rose in reported value and 5 fell.
AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.
Long-equity book
Distinct positions
Filed 2026-08-14
vs 2026-03-31
Portfolio charts
Latest quarter's book, what changed, and how the portfolio has evolved across filings.
Portfolio map
Q2 26Box size = position value; colour = change in share count vs the prior quarter (green added, red trimmed, blue new). Rows split across managers or share classes are combined. Click a box for the stock.
Sector mix
% of 13F valueSectors from each company's SIC code; funds and ETFs grouped separately.
Biggest buys and sells
Q1 26 → Q2 26Estimated from the change in shares held × the quarter-end price, so price moves alone don't count as buying. New and exited positions are included.
13F assets and positions
4 quartersTotal reported 13F value (bars) and number of positions (line) each quarter. Value changes include market moves.
Top positions over time
reported valueThe eight largest current positions, valued at each quarter end.
Concentration
top 10 = 70.3%Cumulative share of the portfolio held in the largest N positions.
BOSTON, MA 02111-2623
| Name | Title / Status | Ownership | Type |
|---|---|---|---|
| CENTRAL SECURITIES CORPORATION Control | SHAREHOLDER | 25–50% | Domestic Entity |
| STONE, JAMES, MARTIN Control | SHAREHOLDER | 25–50% | Individual |
| THE PLYMOUTH ROCK COMPANY INCORPORATED Control | SHAREHOLDER | 75% or more | Domestic Entity |
| BAILEY, JAMES, NATHAN | DIRECTOR | Less than 5% | Individual |
| CHILDS, FREDERICK, CARTER | DIRECTOR AND CHIEF COMPLIANCE OFFICER | Less than 5% | Individual |
| HARTRANFT, WILLIAM, DANIEL | DIRECTOR | Less than 5% | Individual |
| MCELWEE, ANDREW, ALLISON | DIRECTOR | Less than 5% | Individual |
Quarter-over-quarter changes
Changes in reported position value vs the prior 13F, so price moves count too, not just shares bought or sold.
Top Adds (vs prior quarter)
- SELECT SECTOR SPDR TR$115.3M +101.6%
- INTEL CORP$54.3M +57.3%
- SELECT SECTOR SPDR TR$52.1M +958.0%
- SELECT SECTOR SPDR TR$35.7M +731.3%
- WW GRAINGER INC$18.0M +24.7%
Top Trims
- WALMART INC-$54.2M -70.3%
- GE AEROSPACE-$40.6M -47.5%
- TOYOTA MOTOR CORP-$11.0M -18.3%
- PROCTER & GAMBLE CO-$9.4M -27.9%
- COMCAST CORP NEW-$4.6M -14.5%
SRB CORP Holdings (2026-06-30)
Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).
| # | Issuer | Symbol | CUSIP | Value | Weight | Shares | Type |
|---|---|---|---|---|---|---|---|
| 1 | SELECT SECTOR SPDR TR | XLK | 81369Y803 | $154.6M | 8.32% | 811,492 | SH |
| 2 | MICROSOFT CORP | MSFT | 594918104 | $119.5M | 6.43% | 320,422 | SH |
| 3 | RENAISSANCERE HLDGS LTD | RNR | G7496G103 | $98.5M | 5.30% | 310,668 | SH |
| 4 | INTEL CORP | INTC | 458140100 | $92.6M | 4.98% | 663,227 | SH |
| 5 | MICROSOFT CORP | MSFT | 594918104 | $92.5M | 4.97% | 247,966 | SH |
| 6 | SAFETY INS GROUP INC | SAFT | 78648T100 | $76.2M | 4.10% | 1,017,679 | SH |
| 7 | SELECT SECTOR SPDR TR | XLK | 81369Y803 | $74.1M | 3.99% | 388,939 | SH |
| 8 | SAFETY INS GROUP INC | SAFT | 78648T100 | $58.2M | 3.13% | 776,976 | SH |
| 9 | INTEL CORP | INTC | 458140100 | $56.4M | 3.04% | 404,180 | SH |
| 10 | AMAZON COM INC | AMZN | 023135106 | $56.1M | 3.02% | 235,462 | SH |
| 11 | SELECT SECTOR SPDR TR | XLV | 81369Y209 | $52.7M | 2.83% | 332,074 | SH |
| 12 | AMAZON COM INC | AMZN | 023135106 | $51.2M | 2.76% | 214,972 | SH |
| 13 | WW GRAINGER INC | GWW | 384802104 | $49.0M | 2.64% | 36,042 | SH |
| 14 | SELECT SECTOR SPDR TR | XLB | 81369Y100 | $47.0M | 2.53% | 925,356 | SH |
| 15 | SELECT SECTOR SPDR TR | XLC | 81369Y852 | $45.9M | 2.47% | 428,427 | SH |
| 16 | ALPHABET INC | GOOGL | 02079K305 | $43.5M | 2.34% | 121,774 | SH |
| 17 | WW GRAINGER INC | GWW | 384802104 | $41.9M | 2.25% | 30,819 | SH |
| 18 | CVS HEALTH CORP | CVS | 126650100 | $41.0M | 2.21% | 396,796 | SH |
| 19 | SELECT SECTOR SPDR TR | XLB | 81369Y100 | $40.9M | 2.20% | 804,224 | SH |
| 20 | SELECT SECTOR SPDR TR | XLC | 81369Y852 | $39.9M | 2.15% | 372,347 | SH |
| 21 | ALPHABET INC | GOOGL | 02079K305 | $38.3M | 2.06% | 107,094 | SH |
| 22 | SELECT SECTOR SPDR TR | XLV | 81369Y209 | $35.7M | 1.92% | 224,744 | SH |
| 23 | SELECT SECTOR SPDR TR | XLI | 81369Y704 | $31.4M | 1.69% | 169,498 | SH |
| 24 | MERCK & CO INC | MRK | 58933Y105 | $30.2M | 1.62% | 234,641 | SH |
| 25 | MERCK & CO INC | MRK | 58933Y105 | $29.4M | 1.58% | 228,657 | SH |
| 26 | SELECT SECTOR SPDR TR | XLI | 81369Y704 | $26.1M | 1.41% | 141,085 | SH |
| 27 | TOYOTA MOTOR CORP | TM | 892331307 | $24.8M | 1.33% | 147,113 | SH |
| 28 | RENAISSANCERE HLDGS LTD | RNR | G7496G103 | $24.7M | 1.33% | 77,810 | SH |
| 29 | TOYOTA MOTOR CORP | TM | 892331307 | $24.3M | 1.31% | 144,576 | SH |
| 30 | GE AEROSPACE | GE | 369604301 | $23.5M | 1.26% | 62,811 | SH |
| 31 | RELIANCE INC | RS | 759509102 | $21.4M | 1.15% | 57,290 | SH |
| 32 | GE AEROSPACE | GE | 369604301 | $21.3M | 1.15% | 57,114 | SH |
| 33 | COMCAST CORP NEW | CMCSA | 20030N101 | $21.3M | 1.14% | 866,233 | SH |
| 34 | SELECT SECTOR SPDR TR | XLP | 81369Y308 | $21.2M | 1.14% | 254,919 | SH |
| 35 | SHERWIN WILLIAMS CO | SHW | 824348106 | $20.3M | 1.09% | 58,864 | SH |
| 36 | SELECT SECTOR SPDR TR | XLP | 81369Y308 | $19.4M | 1.05% | 233,912 | SH |
| 37 | SHERWIN WILLIAMS CO | SHW | 824348106 | $17.6M | 0.95% | 51,177 | SH |
| 38 | RELIANCE INC | RS | 759509102 | $14.5M | 0.78% | 38,686 | SH |
| 39 | SELECT SECTOR SPDR TR | XLY | 81369Y407 | $13.0M | 0.70% | 110,760 | SH |
| 40 | PROCTER & GAMBLE CO | PG | 742718109 | $12.3M | 0.66% | 83,704 | SH |
| 41 | PROCTER & GAMBLE CO | PG | 742718109 | $12.0M | 0.64% | 81,698 | SH |
| 42 | WALMART INC | WMT | 931142103 | $11.6M | 0.62% | 102,295 | SH |
| 43 | WALMART INC | WMT | 931142103 | $11.3M | 0.61% | 99,953 | SH |
| 44 | CVS HEALTH CORP | CVS | 126650100 | $11.3M | 0.61% | 109,220 | SH |
| 45 | COMCAST CORP NEW | CMCSA | 20030N101 | $5.7M | 0.30% | 230,452 | SH |
| 46 | SELECT SECTOR SPDR TR | XLY | 81369Y407 | $5.1M | 0.28% | 43,780 | SH |
| Period | Filed | AUM | Holdings | Accession |
|---|---|---|---|---|
| 2026-06-30 | 2026-08-14 | $1.86B | 46 | 0000904454-26-000456 |
| 2026-03-31 | 2026-05-14 | $1.63B | 44 | 0000904454-26-000289 |
| 2025-12-31 | 2026-02-13 | $1.82B | 44 | 0000904454-26-000102 |
| 2025-09-30 | 2025-11-14 | $1.74B | 44 | 0000904454-25-000595 |
BOSTON, MA 02111