Jonathan Jay Mazelsky - 12 Feb 2026 Form 4 Insider Report for IDEXX LABORATORIES INC /DE (IDXX)

Reporting relationship: President and CEO, Director
Issuer ticker: IDXX
Reported as of: 12 Feb 2026
Net transaction value: -$575,855
SEC form: 4
Accepted by SEC: 17 Feb 2026, 19:30:58 UTC
Prior SEC filing: 13 Jan 2026
Next SEC filing: 02 Mar 2026
Source filing: View source filing
Reporting owner signature: /s/ Lily J. Lu, Attorney-in-Fact for Jonathan Jay Mazelsky

Key filing fact

Jonathan Jay Mazelsky filed Form 4 for IDEXX LABORATORIES INC /DE (IDXX) on 17 Feb 2026.

Key facts

This page summarizes Jonathan Jay Mazelsky's Form 4 filing for IDEXX LABORATORIES INC /DE (IDXX).
6 reported transactions and 3 derivative rows are listed below.
Accepted by SEC: 17 Feb 2026, 19:30.

Change

Previous filing in this sequence was filed on 13 Jan 2026.
Current net transaction value: -$575,855.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001556270 Primary reporting owner

MAZELSKY JONATHAN JAY

Relationship: President and CEO, Director
Address: ONE IDEXX DRIVE, WESTBROOK
Signature: /s/ Lily J. Lu, Attorney-in-Fact for Jonathan Jay Mazelsky
Signature date: 17 Feb 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

IDXX transaction

Common Stock

Options Exercise

Transaction value: $0
Shares: +958
Change %: +1.2%
Price: $0.000000
Shares after: 83,422
Date: 14 Feb 2026
Ownership: Direct
Footnotes: F1

IDXX transaction

Common Stock

Options Exercise

Transaction value: $0
Shares: +1,099
Change %: +1.3%
Price: $0.000000
Shares after: 84,521
Date: 14 Feb 2026
Ownership: Direct

IDXX transaction

Common Stock

Tax liability

Transaction value: $575,855
Shares: -915
Change %: -1.1%
Price: $629.35
Shares after: 83,606
Date: 14 Feb 2026
Ownership: Direct
Footnotes: F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

IDXX transaction Derivative

Restricted Stock Unit

Award

Transaction value: $0
Shares: +13,407
Change %
Price: $0.000000
Shares after: 13,407
Date: 12 Feb 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 13,407
Exercise price
Footnotes: F3

IDXX transaction Derivative

Restricted Stock Unit

Options Exercise

Transaction value: $0
Shares: -958
Change %: -100%
Price: $0.000000
Shares after: 0
Date: 14 Feb 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 958
Exercise price
Footnotes: F4

IDXX transaction Derivative

Restricted Stock Unit

Options Exercise

Transaction value: $0
Shares: -1,099
Change %: -50%
Price: $0.000000
Shares after: 1,099
Date: 14 Feb 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 1,099
Exercise price
Footnotes: F5

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 5 footnotes

Footnote F1

Includes a total of 21 shares purchased under the Issuer's Employee Stock Purchase Plan ('ESPP') on September 30, 2025 and December 31, 2025. There are a total of 1,943.302 shares held in the ESPP which has been increased by 0.004 shares due to a rounding calculation of previously issued fractional shares.

Footnote F2

Closing price of Issuer common stock on Nasdaq Global Select Market on February 13, 2026.

Footnote F3

Grant of restricted stock units ('RSU') that upon vesting, will be deferred and recorded in an account under the Issuer's Deferred Compensation Plan. This RSU grant vests in three annual installments, beginning February 14, 2027.

Footnote F4

Each RSU represents a contingent right to receive one share of Issuer common stock that vested in four annual installments, beginning February 14, 2023.

Footnote F5

Each RSU represents a contingent right to receive one share of Issuer common stock and vests in four annual installments, beginning February 14, 2024.