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Home/Insiders/MAZELSKY JONATHAN JAY

MAZELSKY JONATHAN JAY

Insider

Insider
Total trades
62
Bought (open market)
$0
Sold (open market)
$40.7M
Acquired (grants)
$101K
Tickers traded
3
Jonathan Jay Mazelsky’s recent SEC Form 4 activity paints a clear picture of a director monetizing equity positions rather than adding new exposure. Across 85 filings spanning three companies, Mazelsky has executed zero open-market purchases while recording approximately $40.7 million in total sales. The overwhelming majority of that selling occurred on February 26, 2026, when he disposed of shares in IDEXX Laboratories (IDXX) across 13 separate transactions. Those sales ranged from roughly $662,000 to $2.4 million each, cumulatively exceeding $13.3 million on that single day. The sales were paired with an option exercise valued at about $3.3 million, a mechanical transaction that supplied the shares sold, along with a smaller exercise worth roughly $99,600 the following day. The pattern is consistent with portfolio diversification rather than a directional bet. Mazelsky’s recent activity in Dentsply Sirona (XRAY) has been limited to compensation-related grants and awards, including a $101,400 grant on June 12, 2026, and smaller awards in January, March, and June. A July 1, 2026, award in Insulet (PODD) carried no reported value. Notably, his most recent 13 filings contain no open-market buys, and the only cash-generating events are the February IDXX sales and a tax-withholding transaction (code “F”) worth roughly $576,000 on February 14, 2026. The absence of any “P” transactions across the entire filing history suggests Mazelsky is not using personal capital to accumulate shares in any of the three companies, despite receiving ongoing equity compensation.

AI-assisted summary

12-month activity

Monthly buy vs sell totals from MAZELSKY JONATHAN JAY's Form 4 filings.

BuysSellsFilings with no price (gifts, grants)
Show data table
MonthBuysSellsFilings
October 2025$0$04
November 2025$0$00
December 2025$0$00
January 2026$0$04
February 2026$0$15.3M19
March 2026$0$01
April 2026$0$00
May 2026$0$00
June 2026$0$03
July 2026$0$01
August 2026$0$00
September 2026$0$00

Recent trades

Most recent Form 4 filings by MAZELSKY JONATHAN JAY.

  • MAZELSKY JONATHAN JAYgranted1,355 shares ofPODDat $0Jul 1 · filed Jul 2Details
  • MAZELSKY JONATHAN JAYgranted2,841.83 shares ofXRAYat $10.56$30KJun 30 · filed Jul 1Details
  • MAZELSKY JONATHAN JAYgranted10,000 shares ofXRAYat $10.14$101KJun 12 · filed Jun 15Details
  • MAZELSKY JONATHAN JAYgranted22,822 shares ofXRAYat $0Jun 3 · filed Jun 5Details
  • MAZELSKY JONATHAN JAYgranted2,644.64 shares ofXRAYat $11.34$30KMar 31 · filed Apr 2Details
  • MAZELSKY JONATHAN JAYexercised197 shares ofIDXXat $505.53$100KFeb 27 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold3,660 shares ofIDXXat $658.917$2.4MFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYexercised23,326 shares ofIDXXat $141.6$3.3MFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold1,281 shares ofIDXXat $650.67$834KFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold1,095 shares ofIDXXat $651.487$713KFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold1,669 shares ofIDXXat $652.495$1.1MFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold1,171 shares ofIDXXat $653.676$765KFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold1,111 shares ofIDXXat $654.629$727KFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold1,488 shares ofIDXXat $655.85$976KFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold1,343 shares ofIDXXat $656.845$882KFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold2,860 shares ofIDXXat $657.844$1.9MFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold2,859 shares ofIDXXat $659.75$1.9MFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold1,200 shares ofIDXXat $661.098$793KFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold1,000 shares ofIDXXat $662.157$662KFeb 26 · filed Mar 2Details
  • MAZELSKY JONATHAN JAYsold2,589 shares ofIDXXat $663.044$1.7MFeb 26 · filed Mar 2Details
View all 62 trades →

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