BLAIR WILLIAM & CO/IL
"13F equity value" = market value of this filer's US-listed long equity positions only. It excludes cash, bonds, non-US and short positions, so it understates a fund's true assets under management — often by a lot.
13F holdings are disclosed ~45 days after quarter-end, and they never reveal when within the quarter a fund actually bought. So any 13F-based summary is structurally late and blurred — this applies to every fund, including this one.
We backtested copying it. Buying this fund's new positions the day each filing went public, over 32 quarters, returned +4.0% per quarter versus +2.7% from owning every 13F stock, beating that baseline in 56.2% of quarters (excess t = 2.49, statistically significant). Caveat: across all 5,072 funds we tested, past performance shows near-zero persistence (rank correlation −0.018) — with thousands of funds, some will look significant by chance alone.
Quarterly compounding, invested quarters only · entry 47 days after quarter-end (when 13F data becomes public)
Top 20 holdings of 1922 · 2026 Q1
| Ticker | Value | Weight | QoQ |
|---|---|---|---|
| AAPL | $1.5B | | HOLD |
| MSFT | $1.3B | | TRIM |
| AMZN | $1.3B | | HOLD |
| NVDA | $947M | | HOLD |
| GOOG | $871M | | TRIM |
| GOOGL | $701M | | TRIM |
| JPM | $679M | | HOLD |
| GEV | $580M | | HOLD |
| V | $558M | | TRIM |
| SPY | $550M | | HOLD |
| IDXX | $532M | | TRIM |
| COST | $519M | | HOLD |
| MA | $461M | | TRIM |
| META | $413M | | HOLD |
| FAST | $342M | | ADD |
| RSP | $323M | | ADD |
| APH | $318M | | TRIM |
| IVV | $317M | | HOLD |
| VEU | $313M | | ADD |
| LLY | $298M | | HOLD |
QoQ vs previous quarter's share count · NEW = new position · ADD/TRIM = ±2% shares · HOLD = unchanged.
New positions in 2026 Q1
Method & Limitations
Method: a "new position" = held this quarter, absent last quarter (options excluded; stocks with <50 prior holders excluded to filter spin-off artifacts). Entry 47 days after quarter-end — the first day the public could act on the filing. Benchmark = equal-weighted universe of all 13F-held stocks. Limitations: quarterly snapshots can't see intra-quarter trades; survivorship bias — funds that shut down are absent, which flatters the sample. Statistics, not advice.