BB BIOTECH AG reported Isis Pharmaceuticals COM (IONS) in 34 quarterly 13F filings .
This page tracks quarterly shares, estimated market value, portfolio weight, filing dates, and disclosure-aligned stock prices directly from SEC EDGAR 13F filings. Older history is available after unlock; the visible window still shows the most recent pattern.
This page is designed to answer the real investor question behind a 13F filing: how meaningful was BB BIOTECH AG's position in Isis Pharmaceuticals COM, 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.
See the most recent quarter where the fund disclosed this position.
Peak weight helps separate a token disclosure from a real conviction holding the fund genuinely cared about.
Longer holding windows often tell a very different story from short-lived tactical trades or one-quarter experiments.
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.
As of 2026 Q1 — sorted by position size
These are the practical questions this page is built to answer before you even open the full history table.
BB BIOTECH AG reported IONS across 0 quarterly 13F filings.
This page shows the quarter-by-quarter portfolio weight history for IONS in BB BIOTECH AG.
The most recent filing on this page is 2019 Q1, when BB BIOTECH AG reported 7,725,000 shares, equal to 15.76% of portfolio, with an estimated market value of $627.0M.
The chart compares BB BIOTECH AG's quarterly IONS 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.
Based on 13F filing dates vs. subsequent IONS price moves, BB BIOTECH AG correctly timed 19 out of 31 reported position changes (61%). The annualised alpha on IONS relative to SPY over the holding period was +14.2%.