Heron Patrick J 4

What Happened

• Patrick J. Heron (Director) reported two acquisitions on 2026-01-23: an open-market purchase of 131,425 shares at $68.48 each for $8,999,984, and an "other acquisition" of 159,277 shares in connection with the merger of Bluejay Therapeutics into Mirum (no cash price listed in the Form 4).
• The merger shares have an implied value based on the Merger effective-date closing price of $94.29 (footnote) — roughly $15.0M in aggregate value for the 159,277 shares. The cash purchase (~$9.0M) represents a direct insider buy; merger consideration reflects a corporate transaction.

Key Details

• Transaction date: 2026-01-23; Form 4 filed 2026-01-27 (filed 4 days after the trades; Form 4 is typically due within 2 business days — may be late).
• Open-market purchase (code P): 131,425 shares @ $68.48 = $8,999,984.
• Other acquisition (code J, merger consideration): 159,277 shares; no purchase price on Form 4. Footnote states closing price on Merger effective date = $94.29 (implied value ≈ $15.0M).
• Shares owned after the transaction: not specified in the provided filing excerpt.
• Ownership structure notes: The merger shares are held by Frazier Life Sciences X, L.P. and Frazier Life Sciences IX, L.P. The reporting person is a managing member of the general partner entities and disclaims beneficial ownership except to the extent of his pecuniary interest (Footnotes F1–F3).

Context

• The filing shows a significant open-market purchase (direct cash outlay of about $9.0M) plus receipt of shares from a merger; purchases are often of interest to retail investors as one data point on insider sentiment, while merger consideration reflects transaction mechanics rather than a market purchase.
• This is not an option exercise, gift, or 10b5-1 sale; it involves both a market purchase and institutional-held merger shares.