David W. J. McGirr

Companies

• X4 Pharmaceuticals, IncBoard member Nov 15, 2017 to now¹
• Rhythm (United states)Board member Oct 4, 2017 to now²
• INSMED IncBoard member Nov 1, 2013 to now³
• Yarrow Bioscience, Inc.Board member Jan 24, 2018 to Aug 8, 2019⁴
• Cubist PharmaceuticalsChief financial officer Jan 10, 2006 to Feb 20, 2013⁵

Holdings

Stock this person has reported owning, from the forms officers and directors file with the SEC. See the biggest insider stakes.

Shares held

• IINSMED Inc INSM97,723 shares⁶$9.3M at $95.67Feb 9, 2026
• RURhythm (United states) RYTM11,712 shares⁷$1.0M at $88.25Jun 23, 2026
• XPX4 Pharmaceuticals, Inc XFOR4,722 shares⁸$12.1K at $2.56Jun 9, 2025

As of each latest filing. The line shows shares held over time.

Recent filings

• Jun 23, 2026Exercised options 4,712 shares of Rhythm (United states)⁷
• Feb 9, 2026Gift 53,400 shares of INSMED Inc⁶
• Feb 9, 2026Gift 53,400 shares of INSMED Inc⁶
• Jun 18, 2025Exercised options 4,000 shares of Rhythm (United states)⁹
• Jun 9, 2025Granted 1,500 shares of X4 Pharmaceuticals, Inc⁸
• Jun 4, 2025Sold 3,000 shares at $73.27 of INSMED Inc¹⁰
• Jun 3, 2025Sold 9,873 shares at $65.64 of Rhythm (United states)¹¹
• Jun 3, 2025Sold 55,558 shares at $65.15 of Rhythm (United states)¹¹
• Jun 3, 2025Sold 3,250 shares at $71.30 of INSMED Inc¹⁰
• Jun 3, 2025Exercised options 65,431 shares at $4.59 of Rhythm (United states)¹¹
• May 15, 2025Granted 5,058 shares of INSMED Inc¹²
• Jun 21, 2024Exercised options 3,000 shares of Rhythm (United states)¹³
• Jun 10, 2024Granted 45,000 shares of X4 Pharmaceuticals, Inc¹⁴
• May 13, 2024Granted 13,162 shares of INSMED Inc¹⁵
• Jun 13, 2023Granted 45,000 shares of X4 Pharmaceuticals, Inc¹⁶
• May 11, 2023Granted 13,192 shares of INSMED Inc¹⁷
• Jun 6, 2022Granted 6,667 shares of X4 Pharmaceuticals, Inc¹⁸
• May 11, 2022Granted 14,645 shares of INSMED Inc¹⁹