Institutional Manager · CIK 0001579254
East Coast Asset Management, LLC.
ESSEX, MA · File #028-15537
Latest AUM
$340.0M
Positions
69
Top-10 Concentration
74.5%
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 |
|---|---|---|---|---|---|
| NEW | ECHOSTAR CORP | SATS | +137,244 | +$14.9M | $0 |
| REDUCE | META PLATFORMS INC | META | -20,025 | -$13.2M | -$3.1M |
| ADD | TESLA INC | TSLA | +13,173 | +$5.9M | +$342,110 |
| REDUCE | PERIMETER SOLUTIONS INC | PRM | -207,593 | -$5.7M | +$8.1M |
| EXITED | CHARTER COMMUNICATIONS INC N | 16119P108 | -9,643 | -$2.7M | $0 |
| REDUCE | ALPHABET INC | GOOG | -4,099 | -$1.3M | +$14.1M |
| REDUCE | BERKSHIRE HATHAWAY INC DEL | BRK-A | -1,104 | -$554,931 | -$2,847 |
| ADD | FIDELITY WISE ORIGIN BITCOIN | FBTC | +5,205 | +$396,777 | -$55,294 |
| ADD | MICROSOFT CORP | MSFT | +779 | +$376,775 | -$258,083 |
| NEW | PROFESIONALLY MANAGED PORTFO | 74316P579 | +4,889 | +$320,278 | $0 |
Sector Allocation
Filing History
- 13F HOLDINGS REPORTQ/E Dec 202569 pos · $340.0M
- 13F HOLDINGS REPORTQ/E Sep 202568 pos · $319.2M
- 13F HOLDINGS REPORTQ/E Jun 202569 pos · $301.4M
- 13F HOLDINGS REPORTQ/E Mar 202569 pos · $282.4M
- 13F HOLDINGS REPORTQ/E Dec 202471 pos · $299.3M
- 13F HOLDINGS REPORTQ/E Sep 202473 pos · $301.2M
- 13F HOLDINGS REPORTQ/E Jun 202470 pos · $275.1M
- 13F HOLDINGS REPORTQ/E Mar 202469 pos · $274.1M
- 13F HOLDINGS REPORTQ/E Dec 202362 pos · $221.0M
Top 20 Holdings — Dec 2025
| # | Issuer | Ticker | Shares | Value | % of Portfolio |
|---|---|---|---|---|---|
| 1 | ALPHABET INC | GOOG | 196,119 | $61.5M | 18.38% |
| 2 | PERIMETER SOLUTIONS INC | PRM | 1,366,380 | $37.6M | 11.23% |
| 3 | TESLA INC | TSLA | 81,595 | $36.7M | 10.96% |
| 4 | TRANSDIGM GROUP INC | TDG | 23,341 | $31.0M | 9.27% |
| 5 | BERKSHIRE HATHAWAY INC DEL | BRK-A | 30,591 | $15.4M | 4.59% |
| 6 | ECHOSTAR CORP | SATS | 137,244 | $14.9M | 4.46% |
| 7 | META PLATFORMS INC | META | 21,842 | $14.4M | 4.31% |
| 8 | AMAZON COM INC | AMZN | 60,410 | $13.9M | 4.16% |
| 9 | MASTERCARD INCORPORATED | MA | 23,242 | $13.3M | 3.96% |
| 10 | APPLE INC | AAPL | 39,610 | $10.8M | 3.22% |
| 11 | WOODWARD INC | WWD | 29,040 | $8.8M | 2.62% |
| 12 | MOODYS CORP | MCO | 14,235 | $7.3M | 2.17% |
| 13 | TJX COS INC NEW | 872540109 | 45,657 | $7.0M | 2.09% |
| 14 | VISA INC | V | 16,232 | $5.7M | 1.70% |
| 15 | DEERE & CO | DE | 10,242 | $4.8M | 1.42% |
| 16 | MARKEL GROUP INC | MKL | 2,096 | $4.5M | 1.35% |
| 17 | SCHWAB CHARLES CORP | SCHW-PJ | 44,986 | $4.5M | 1.34% |
| 18 | MICROSOFT CORP | MSFT | 8,310 | $4.0M | 1.20% |
| 19 | SPDR S&P 500 ETF TR | SPY | 5,041 | $3.4M | 1.03% |
| 20 | SHERWIN WILLIAMS CO | SHW | 10,468 | $3.4M | 1.01% |