Port Capital LLC
SEC Form 13F institutional filer · CIK 0001729212
13F-HR · 51 reported holdings · 2026-03-31
SEC-registered institutional investment manager.
Reported long-US-equity value
$1.15B
Top-10 concentration
70.0%
Port Capital LLC — $1.15B AUM allocation strategy
Port Capital LLC files SEC Form 13F and reports $1.15B of long US equity value across 51 reported holdings for 2026-03-31.
Its largest sector bet is Industrials 28.7%, followed by Financials 26.0% and Information Technology 23.2%.
The top 10 holdings account for 70% of reported value — a conviction-weighted book concentrated in its best ideas. The sector and industry splits below are of the same reported value. Track quarter-over-quarter adds, trims, new positions and exits below — sourced from SEC 13F filings, public domain.
Port Capital LLC — latest SEC 13F insights
Reported long-US-equity value (13F AUM)
$1.15B
total across 51 reported holdings · 2026-03-31 · excludes shorts, cash, non-US
Top-10 concentration
70% of value
higher = narrower conviction; lower = spread / hedging
Biggest adds (shares)
+$AXP +62.1K sh · +$16.6M+$CPRT +51.4K sh · −$6.9M+$CMI +32K sh · +$6.08M
Biggest trims (shares)
−$APH −116K sh · −$22.8M−$ACGL −64.1K sh · −$6.12M−$SPGI −49.5K sh · −$28.6M
Exited to nil (held last quarter, gone now)
$BRO ($21.5M last qtr)$ADP ($19.2M last qtr)$UNH ($10M last qtr)$META ($302K last qtr)
Sector allocation (share of reported value)
each slice is a share of the reported long-US-equity value — smaller sectors and the rest of the book roll into “Other holdings”
Qtr shift = share-point change vs the prior quarter's filing — first period tracked for this filer; the column fills in with the next quarterly refresh.
Industry allocation (share of reported value)
- Electronic Equipment & Instruments13.3%—
- Electrical Components & Equipment11.4%—
- Electronic Components8.9%—
- Property & Casualty Insurance8.5%—
- Industrial Machinery & Supplies & Components8.5%—
- Automotive Retail7.6%—
- Transaction & Payment Processing Services7.4%—
- Industrial Gases7.4%—
- Other holdings27.0%—
the finer GICS cut of the same book — same denominator — smaller industries roll into “Other holdings”
Qtr shift = share-point change vs the prior quarter's filing — first period tracked for this filer; the column fills in with the next quarterly refresh.
Top S&P 500 holdings
10 of 10 rows · sorted by Value ↓
| Ticker | Holding | Shares | Value | Δ QoQ | Weight |
|---|---|---|---|---|---|
| $TDY | Teledyne Technologies Incorporated | 251K | $152M | +14.4K | 13.2% |
| $APH | Amphenol Corporation | 813K | $103M | -116K | 8.9% |
| $AME | AMETEK Inc | 432K | $92.7M | -19.5K | 8.1% |
| $ORLY | O'Reilly Automotive Inc | 943K | $87M | -32.6K | 7.6% |
| $LIN | Linde plc | 171K | $84.7M | -5.83K | 7.4% |
| $PH | Parker-Hannifin Corporation | 84.6K | $75.8M | -4.11K | 6.6% |
| $ICE | Intercontinental Exchange Inc | 366K | $57.6M | -15.1K | 5.0% |
| $CMI | Cummins Inc | 909K | $51.6M | +32K | 4.5% |
| $CPRT | Copart Inc | 1.5M | $49.7M | +51.4K | 4.3% |
| $MA | Mastercard Incorporated | 98.9K | $49.4M | -12K | 4.3% |
…and 41 more holdings in the full 13F filing (top positions only shown).
SEC Form 13F data sets · public domain · 45-day filing lag · >$100M AUM managers · as reported
← All 13F filers·← QuantOrb.pro
How to read Δ QoQ — the five insight categories, and the caveats
The categories. Analysts, quants and retail traders look past total portfolio value to isolate actionable signals. Five categories matter.
Conviction & concentration shifts
New positions vs complete exits — a brand-new stock signals high conviction; a full liquidation suggests a broken thesis or tax-loss harvesting. Aggressive sizing — look at share count, not dollars: a 20% share increase during a drawdown is strong dip-buying. Concentration — a narrowing top-5/10 means conviction; spreading capital across more names means hedging.
Sector & macro allocation rotations
Aggregating Δ QoQ moves across sectors shows where smart money is leaning in or sneaking out — rotating out of growth into defensives or energy, for example. The fund's total long equity exposure quarter-over-quarter is a proxy for overall institutional risk appetite.
Crowding & smart-money consensus
When several managers initiate or expand the same stock in the same quarter, that is institutional consensus. Contrarian reads: top pickers buying hard into a beaten-down name the market is selling.
Derivative & option overlays
Reported call/put changes indicate whether managers are adding downside hedges or leveraging upside exposure. Note: a long increase may be half of a market-neutral pair trade.
Who reads this
| Retail "cloners" | High-conviction ideas to replicate ~45 days after quarter-end. |
| Corporate IR | Which funds bought or dumped the stock, before the next call. |
| Quant / algo traders | Cross-sectional factor inputs: flow, momentum, ownership. |
Four caveats before you trade on it
- 45-day lag — holdings are quarter-end; positions may already be closed.
- Long-only — 13Fs miss shorts, pair trades and cash.
- No non-US / fixed income — the picture is US equities plus options.
- Corporate actions — splits and spinoffs distort raw share deltas.
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