Harbor Island Capital LLC
SEC Form 13F institutional filer · CIK 0001730580
13F-HR · 13 reported holdings · 2026-03-31
Reported long-US-equity value
$0.24B
Top-10 concentration
92.4%
Harbor Island Capital LLC — $236M AUM allocation strategy
Harbor Island Capital LLC files SEC Form 13F and reports $236M of long US equity value across 13 reported holdings for 2026-03-31.
Its largest sector bet is Information Technology 65.8%, followed by Communication Services 17.1% and Financials 11.6%.
The top 10 holdings account for 92% 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.
Harbor Island Capital LLC — latest SEC 13F insights
Reported long-US-equity value (13F AUM)
$236M
total across 13 reported holdings · 2026-03-31 · excludes shorts, cash, non-US
Top-10 concentration
92% of value
higher = narrower conviction; lower = spread / hedging
Biggest trims (shares)
−$LRCX −41.2K sh · −$261K−$AMAT −11.5K sh · +$7.07M−$WBD −10.1K sh · −$1.61M
Added from nil (new positions)
None this quarter
Exited to nil (held last quarter, gone now)
None this quarter
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)
- Semiconductor Materials & Equipment40.0%—
- Diversified Banks11.6%—
- Broadcasting11.3%—
- Technology Hardware, Storage & Peripherals10.8%—
- Communications Equipment6.8%—
- Systems Software6.0%—
- Cable & Satellite5.8%—
- Apparel, Accessories & Luxury Goods5.4%—
- Other holdings2.3%—
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 |
|---|---|---|---|---|---|
| $AMAT | Applied Materials Inc | 118K | $40.4M | -11.5K | 17.1% |
| $LRCX | Lam Research Corporation | 160K | $34.1M | -41.2K | 14.5% |
| $WBD | Warner Bros. Discovery Inc. Series A | 971K | $26.7M | -10.1K | 11.3% |
| $WFC | Wells Fargo & Company | 254K | $20.2M | +0 | 8.6% |
| $KLAC | KLA Corporation | 13.6K | $20M | +0 | 8.5% |
| $AAPL | Apple Inc | 78.6K | $19.9M | +0 | 8.4% |
| $CSCO | Cisco Systems Inc | 206K | $16M | +0 | 6.8% |
| $MSFT | Microsoft Corporation | 38.5K | $14.3M | +0 | 6.0% |
| $CMCSA | Comcast Corporation | 480K | $13.8M | +0 | 5.8% |
| $NKE | Nike Inc | 243K | $12.8M | +46K | 5.4% |
…and 3 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.
Newsletter signup
Free subscription. Daily trading day morning dispatch. No spam.