S&CO INC — 13F Holdings & Portfolio

CIK 1082461 · latest 13F-HR filed 2026-08-06

S&CO INC manages $1.7M in 13F-reported U.S. long-equity assets across 222 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are CAT (5.79%), BRK.B (4.74%), MSFT (4.27%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 14 new positions, exited 10, added to 114, and trimmed 56.

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.

Filer Information
Address
50 CONGRESS STREET ROOM 800
BOSTON, MA 02109
Phone
(617) 227-8660
Filing Manager
S&CO INC
BOSTON, MA
Signatory
Jason Ries
Operations
Loading holdings…
AUM

$1.7M

Long-equity book

Holdings

222

Distinct positions

Period

2026-06-30

Filed 2026-08-06

Q/Q Activity

+14 / −10 / ↑114 / ↓56

vs 2026-03-31

Firm Profile & Key People
Name Title / Status Ownership Type

Top Adds (vs prior quarter)

  • CATERPILLAR INC.$30.2K +43.1%
  • PALO ALTO NETWORKS INC$17.4K +124.8%
  • ALPHABET INC CLASS C$7.9K +23.2%
  • ELI LILLY & CO COM$7.0K +35.1%
  • ALPHABET INC CAP STK CL A$6.6K +24.0%
Show all 114

Top Trims

  • SPDR GOLD TRUST-$5.0K -14.4%
  • LIBERTY LATIN AMERICA-CL A-$4.1K -76.7%
  • CAMECO CORP-$3.6K -10.2%
  • ABBOTT LABS-$3.6K -17.5%
  • DIGITALBRIDGE GROUP INC-$3.4K -94.8%
Show all 56

New Positions

  • EXXONMOBIL HOLDINGS CORP$71.9K
  • CF INDUSTRIES HOLDINGS INC COM$2.6K
  • REDDIT, INC. CLASS A$2.0K
  • UBER TECHNOLOGIES INC$1.7K
  • MERCADOLIBRE, INC.$1.5K
Show all 14

Exited Positions

  • EXXON MOBIL CORP$89.2K
  • COGNIZANT TECHNOLOGY SOLUTIONS$1.8K
  • HONEYWELL INTERNATIONAL INC CO$1.3K
  • ULTRAGENYX PHARMACEUTICAL, INC$529
  • IQVIA HOLDINGS INC$511
Show all 10
All Holdings

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 CATERPILLAR INC. CAT 149123101 $100.2K 5.79% 94,076 SH
2 BERKSHIRE HATHAWAY INC CL B BRK.B 084670702 $82.1K 4.74% 164,075 SH
3 MICROSOFT CORP MSFT 594918104 $74.0K 4.27% 198,340 SH
4 EXXONMOBIL HOLDINGS CORP XOM 30233Q108 $71.9K 4.15% 526,003 SH
5 APPLE INC AAPL 037833100 $63.9K 3.69% 220,707 SH
6 CHURCH & DWIGHT CO INC CHD 171340102 $62.9K 3.64% 649,655 SH
7 ECOLAB INC ECL 278865100 $62.9K 3.64% 225,862 SH
8 MERCK & CO INC MRK 58933Y105 $54.7K 3.16% 425,528 SH
9 AMAZON.COM INC AMZN 023135106 $46.9K 2.71% 196,975 SH
10 AUTOMATIC DATA PROCESSING INC ADP 053015103 $45.2K 2.61% 201,978 SH
11 ALPHABET INC CLASS C GOOG 02079K107 $41.7K 2.41% 118,113 SH
12 JOHNSON & JOHNSON JNJ 478160104 $39.9K 2.30% 157,098 SH
13 ALPHABET INC CAP STK CL A GOOGL 02079K305 $33.9K 1.96% 94,857 SH
14 CAMECO CORP CCJ 13321L108 $31.9K 1.85% 313,626 SH
15 PALO ALTO NETWORKS INC PANW 697435105 $31.3K 1.81% 91,852 SH
16 SPDR GOLD TRUST GLD 78463V107 $29.7K 1.71% 80,565 SH
17 AIR PRODUCTS & CHEMICALS INC C APD 009158106 $27.7K 1.60% 94,594 SH
18 ELI LILLY & CO COM LLY 532457108 $26.7K 1.55% 22,300 SH
19 MOSAIC COMPANY MOS 61945C103 $22.1K 1.27% 1,040,723 SH
20 PROSUS NV -SPON ADR PROSF 74365P108 $21.7K 1.25% 2,499,611 SH
21 THERMO FISHER SCIENTIFIC INC C TMO 883556102 $20.7K 1.20% 41,387 SH
22 ROYALTY PHARMA PLC CL A RPRX G7709Q104 $20.1K 1.16% 358,302 SH
23 UNION PACIFIC CORP UNP 907818108 $18.9K 1.09% 69,353 SH
24 PAYPAL HOLDINGS INC PYPL 70450Y103 $18.8K 1.09% 436,017 SH
25 LIBERTY MEDIA CORP-LIBERTY LIV LLYVK 530909308 $18.5K 1.07% 174,783 SH
26 UNITEDHEALTH GROUP INC COM UNH 91324P102 $18.3K 1.06% 43,984 SH
27 ANTERO RESOURCES CORP AR 03674X106 $17.7K 1.02% 504,602 SH
28 ABBOTT LABS ABT 002824100 $16.9K 0.98% 186,521 SH
29 SIRIUS XM HOLDINGS INC SIRI 829933100 $16.8K 0.97% 569,206 SH
30 EVERPURE, INC. CLASS A P 74624M102 $15.0K 0.87% 190,420 SH
31 SPDR S&P BIOTECH ETF XBI 78464A870 $14.9K 0.86% 94,310 SH
32 NVIDIA CORP COM NVDA 67066G104 $14.4K 0.83% 72,156 SH
33 VISA INC. CL A V 92826C839 $14.4K 0.83% 41,890 SH
34 H.B. FULLER CO. FUL 359694106 $14.1K 0.81% 241,781 SH
35 GE VERNOVA INC GEV 36828A101 $13.8K 0.80% 11,732 SH
36 LINDE PLC LIN G54950103 $13.6K 0.78% 26,139 SH
37 GE AEROSPACE COM (NEW) GE 369604301 $13.3K 0.77% 35,671 SH
38 ALKERMES PLC ALKS G01767105 $12.8K 0.74% 244,760 SH
39 CISCO SYSTEMS INC COM CSCO 17275R102 $12.6K 0.73% 107,126 SH
40 ROCHE HOLDING LTD SPONSORED AD RHHBY 771195104 $11.9K 0.69% 230,310 SH
41 LIBERTY FORMULA ONE SER C FWONK 531229755 $11.7K 0.67% 122,528 SH
42 MASTERCARD INC - A MA 57636Q104 $11.5K 0.66% 22,358 SH
43 GFL ENVIRONMENTAL GFL 36168Q104 $10.8K 0.62% 293,524 SH
44 PEPSICO INC PEP 713448108 $10.2K 0.59% 75,677 SH
45 AFLAC INC COM AFL 001055102 $9.8K 0.57% 83,570 SH
46 ANALOG DEVICES INC COM ADI 032654105 $9.4K 0.55% 23,789 SH
47 AIRBNB INC A ABNB 009066101 $8.9K 0.52% 62,355 SH
48 MEDTRONIC PLC MDT G5960L103 $8.5K 0.49% 108,128 SH
49 VANGUARD FTSE EMERGING MARKET VWO 922042858 $7.9K 0.46% 132,538 SH
50 JP MORGAN CHASE & CO JPM 46625H100 $7.6K 0.44% 23,285 SH
Filing History
Period Filed AUM Holdings Accession
2026-06-30 2026-08-06 $1.7M 222 0001082461-26-000003
2026-03-31 2026-05-07 $1.6M 218 0001082461-26-000002
2025-12-31 2026-02-05 $1.6M 218 0001082461-26-000001