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OBERNDORF WILLIAM E

Location
San Francisco, CA
Portfolio Value
Micro $55,022,949
Diversification
Moderately concentrated
Filing Date
Global Rank
#8,548 / 8,814 ▼ 117
Top Industry
Healthcare Plans 26.9%
3Y Alpha vs SPY
-2.9%
Period ended 4 months ago
Filed Aug 13, 2026 · 2mo
26 quarters · since Mar 2020

Regulatory profile

From Form ADV, the SEC filer profile, 13D/13G type codes and N-CEN, never from the name.

Holder type
Unknown

Portfolio style

Measured from the filed 13F common-share book for Jun 30, 2026, never from the firm's own description.

Style
Concentrated
The top 10 positions are 100.0% of the book (60%+)
Turnover
Medium turnover
54.0% over the last four quarters (30% to under 100%)
Horizon
Medium horizon
Value-weighted holding period 6.2 quarters (4 to under 12)

Closest benchmark: the Dow Jones Industrial Average as of 2026-07-31, active share 88.2%; sector active share 40.7% against the combined 13F book's sector weights.

Over time 26 measured quarters

How the bands are measured

Style bands measure the filed 13F common-share book each closed quarter, tested in this order. Unknown: under $10,000,000 of valued equity or 5 stocks. Index-like (100+ stocks): active share of 20% or less against the closest benchmark, which is the S&P 500, S&P MidCap 400, S&P SmallCap 600, Russell 1000, Russell 2000, Nasdaq-100 or Dow Jones Industrial Average (weighted by an index-tracking fund's reported holdings or the index's constituents nearest the quarter end, over the names resolved to companies, and only when those are 90%+ of its weight) or every 13F filer's combined book, or index series holding 80%+ of the registered fund assets it advises (N-CEN) and equal to 50%+ of its book. Systematic-like: 500+ stocks, 100%+ annual turnover and a top 10 weight of 25% or less. Concentrated: a top 10 weight of 60%+ or 12 or fewer effective positions. Diversified active: none of these. Turnover is the smaller of buys and sells over average equity value, summed over four quarters: low under 30%, high 100%+. Horizon is the value-weighted number of quarters each position has been held: short under 4, long 12+.

Clone Performance

Build a hypothetical price-return history from this filer's public 13F holdings.

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Portfolio Concentration

8 tracked positions · as of Jun 30, 2026 · Δ vs Mar 31, 2026
Top Position
26.9%
+8.8 pts
Top 5
85.4%
+6.2 pts
Top 10
100.0%
0.0 pts
HHI
1,680
Sep 2023 → Jun 2026 · range 1,348 – 2,099
Moderately concentrated+194

Portfolio Trend

26 quarters · across all stocks

Sector Breakdown

As of Jun 30, 2026
Sector % Portfolio Value
Healthcare 41.4% $22,790,195
Technology 22.5% $12,379,798
Consumer Cyclical 15.6% $8,587,628
Financial Services 12.3% $6,771,324
Communication Services 8.2% $4,494,004

Last Quarter's Activity

Export CSV
Jun 30, 2026 vs Mar 31, 2026

Added To

Positions the filer increased
1 positions
Ticker Δ Shares Shares Value Open

Trimmed

Positions the filer reduced
1 positions
Ticker Δ Shares Shares Value Open

New Positions

Positions the filer opened this quarter
2 positions
Ticker Shares Value Open

Sold Out

Positions the filer fully exited
1 positions
Ticker Shares Value Open

Portfolio Positions

Export CSV View 13F filing
8 tracked positions · $55,022,949 total · filing declares 8 positions · $55,022,953 · as of Jun 30, 2026
Ticker Company Shares Value (USD) % of Portfolio History

Covers the securities this platform tracks: U.S.-listed common stock and the put/call positions reported on it. A 13F can also report security types outside that coverage — preferred shares, bonds, warrants, untracked share classes — so the filing's own declared total can exceed the figures above. The source filing is linked at the top of this table.