William Mack & Associates, Inc. VRTX VERTEX PHARMACEUTICALS INC

Ownership history in William Mack & Associates, Inc.  ·  4 quarters on record

AI Ownership Summary

William Mack & Associates, Inc. reported VERTEX PHARMACEUTICALS INC (VRTX) in 4 quarterly 13F filings from 2025 Q3 through 2026 Q2. Peak portfolio weight reached 0.17% in 2026 Q1. The latest visible filing shows VRTX at 0.11% of the fund.

This page tracks quarterly shares, estimated market value, portfolio weight, filing dates, and disclosure-aligned stock prices directly from SEC EDGAR 13F filings.

What this VRTX ownership page tells you

This page is designed to answer the real investor question behind a 13F filing: how meaningful was William Mack & Associates, Inc.'s position in VERTEX PHARMACEUTICALS INC, and how did that conviction change over time? You can read the holding window, peak weight, latest reported size, disclosure timing, and quarter-by-quarter changes without piecing the story together from raw SEC rows.

Freshest filing
Latest Reported Filing
2026 Q2

VRTX was reported at 0.11% of portfolio in the most recent visible filing.

High-water mark
Peak Conviction
0.17% in 2026 Q1

Peak weight helps separate a token disclosure from a real conviction holding the fund genuinely cared about.

Time in book
Holding Window
2025 Q3 to 2026 Q2

Longer holding windows often tell a very different story from short-lived tactical trades or one-quarter experiments.

Decision context
Why It Matters
Position size beats headlines

Knowing that a fund owned a stock is useful. Knowing whether it was a 0.20% placeholder or a true high-conviction position is where the signal actually starts.

How William Mack & Associates, Inc. held VRTX — position size vs. price
% of Fund (quarterly)    VRTX price (quarter-end, indexed to 100)    SPY (indexed to 100)    QQQ (indexed to 100)
📋 Quarterly Holdings History 4 quarters  
Quarter Action Sold % After 3M Timing Shares Change Chg % % of Fund Mkt Value Filed Price (Filed)
2026 Q2 REDUCED 630 -39 -5.8% 0.11% $313K 2026-07-10 $485.39
2026 Q1 REDUCED 669 -13 -1.9% 0.17% $299K 2026-04-14 $444.28
2025 Q4 UNCHANGED 682 0% 0.15% $309K 2026-02-09 $470.87
2025 Q3 INITIATED 682 0.14% $267K 2025-11-14 $437.15

FAQ About William Mack & Associates, Inc. and VRTX

These are the practical questions this page is built to answer before you even open the full history table.

How long has William Mack & Associates, Inc. reported owning VRTX?

William Mack & Associates, Inc. reported VRTX across 4 quarterly 13F filings, from 2025 Q3 through 2026 Q2.

What was the largest reported VRTX position in William Mack & Associates, Inc.'s portfolio?

The largest reported portfolio weight for VRTX was 0.17% in 2026 Q1.

What is the latest reported VRTX position on this page?

The most recent filing on this page is 2026 Q2, when William Mack & Associates, Inc. reported 630 shares, equal to 0.11% of portfolio, with an estimated market value of $313K.

What does the chart on this VRTX ownership page compare?

The chart compares William Mack & Associates, Inc.'s quarterly VRTX portfolio weight with the stock's indexed share price, so you can see whether the fund was building, trimming, or holding the position as price moved.

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