Bill Ackman 13F Tracker & Pershing Mirror Calculator
Mirror calculator example
The pershing square holdings calculator tool divides an amount across the largest long positions in proportion to their 13F weights and converts each allocation into whole shares at the quarter-end price implied by the filing. Here is the split of $10,000 across the top five long positions of the latest filing:
| Security | Weight in split | Allocation | Quarter-end price | Whole shares |
|---|---|---|---|---|
| UBER | 22.0% | $2,197 | $72.16 | 30 |
| BN | 21.7% | $2,172 | $42.59 | 50 |
| MSFT | 20.5% | $2,054 | $373.02 | 5 |
| AMZN | 18.1% | $1,811 | $238.34 | 7 |
| HHH | 17.7% | $1,766 | $71.49 | 24 |
What does the Ackman tracker show?
Every reported Pershing Square position for the quarter you pick, with share count, value, weight and the change from the prior quarter, plus concentration measures and a calculator that splits an amount across the largest holdings by 13F weight.
How concentrated is Pershing Square?
In the latest filing the largest position is 12.7% of reported value, the top five 57.9% and the top ten 93.5%, across 14 positions. Over the stored quarters the fund held between 11 and 14 US-listed positions.
Is the mirror calculator advice?
No. It is arithmetic on public data: it applies 13F weights and quarter-end prices to your amount. It ignores the 45-day filing delay, trades since quarter end, fees and taxes, and it cannot copy Pershing's hedges.
How the Bill Ackman 13F portfolio tracker works
This bill ackman 13f portfolio tracker is built from the information tables that Pershing Square files on SEC EDGAR every quarter. Gemral Edge stores each filing once per quarter, adds up the lines for the same security and position type, and calculates weights against the total reported value. Choosing a quarter updates the headline numbers, the holdings table and the change column together, and the selection is kept in the page address so a view can be bookmarked or shared.
One detail matters for anyone comparing quarters. From the quarter ended June 30, 2026 the holdings are reported by Pershing Square Inc., which the adviser's 13F notice describes as its public parent company. Earlier quarters come from Pershing Square Capital Management, L.P. The tool follows that change automatically, so the history remains continuous.
Reading the change column
Each holding is compared with the previous stored quarter by share count. "New" means the position did not appear before, "Added" and "Trimmed" show the percentage change in shares, and positions sold completely are listed under the table. Because values move with share prices, a change in weight alone can hide whether Ackman actually traded; share counts avoid that problem. Used this way the table works as a bill ackman stock portfolio screener: you can see at a glance which names he is building and which he is reducing.
Concentration, measured
Concentration is the defining feature of the fund, so the tool shows the cumulative weight of the largest one, three, five and ten positions. A reading of 57.9% for the top five means that this share of the reported portfolio rises or falls with just five companies. That is useful context before copying any single idea: a position that is small in Pershing's book may still be a large bet for an individual investor.
Computed by the same engine as the interactive tool from the filing for the quarter ended June 30, 2026. Prices are value divided by shares at quarter end, not current market quotes.
An activist investor portfolio tracker, with limits
Pershing Square built its reputation on activism, taking large stakes and pressing for change, and it still has that character in Howard Hughes Holdings, where it is the largest shareholder. As an activist investor portfolio tracker tool, the tracker shows the size of such stakes and how they change, but it cannot show board seats, private negotiations or the terms of a deal. Those appear in Schedule 13D filings and company announcements, which are worth reading alongside the 13F.
What the data leaves out
- 13F filings are due 45 days after quarter end and show a single quarter-end snapshot.
- Short positions in stock, credit and index hedges, cash, bonds and most non-US securities are excluded.
- Purchase prices and trading dates are not disclosed.
- The mirror split ignores fees, taxes, fractional shares and price moves after quarter end.
Related pages
Read the full Pershing Square 13F guide for the quarter-by-quarter story, compare with the Berkshire Hathaway 13F tracker and the Michael Burry 13F tracker, or browse the superinvestor directory. AI agents can query the same data through the WebMCP action track-bill-ackman-pershing-square-13f-portfolio.