Mesa Laboratories Inc
MLAB- Exchange
- Nasdaq
- Industry
- Industrial Instruments For Measurement, Display, and Control
- SEC CIK
- 0000724004
In the last 90 days, Mesa Laboratories Inc insiders filed 2 open-market purchases and 1 sale; 159 institutions reported holding it in 13F filings for Q2 2026, worth $500.8M in total; no superinvestor holds it.
Holders of 5% or more of MLAB
Holders whose latest Schedule 13D or 13G filing reports 5% or more of Mesa Laboratories Inc, largest stake first. The change is against the holder's previous filing.
| Holder | Latest form | Stake | Change | First filed | Latest filing | Filing |
|---|---|---|---|---|---|---|
| Conestoga Capital Advisors, LLC | 13G/A | 11.38%618.1K shares | – | Jan 10, 20251 filing | Jan 10, 2025 | SEC |
| BlackRock, Inc. | 13G/A | 6.90%378.9K shares | −7.50 ppfrom 14.40% | Jul 18, 20252 filings | Oct 2, 2025 | SEC |
| Vanguard Group Inc | 13G/A | 5.84%321.7K shares | – | Oct 31, 20251 filing | Oct 31, 2025 | SEC |
Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.
13D and 13G filings
6 Schedule 13D and 13G filings on Mesa Laboratories Inc, newest first, including old-format filings without a stake.
| Filed (ET) | Filer | Form | Stake | Change | Event date | Filing |
|---|---|---|---|---|---|---|
| Oct 31, 202511:02 AM ET | Vanguard Group Inc | 13G/A | 5.84%321.7K shares | – | Sep 30, 2025 | SEC |
| Oct 2, 20256:46 PM ET | BlackRock, Inc. | 13G/A | 6.90%378.9K shares | −7.50 ppfrom 14.40% | Sep 30, 2025 | SEC |
| Jul 18, 202512:06 PM ET | BlackRock, Inc. | 13G/A | 14.40%783.0K shares | – | Jun 30, 2025 | SEC |
| Apr 30, 202511:44 AM ET | Royce & Associates LP | 13G/A | 4.99%271.1K shares | −0.30 ppfrom 5.29%Below 5% | Mar 31, 2025 | SEC |
| Jan 28, 202511:55 AM ET | Royce & Associates LP | 13G/A | 5.29%287.2K shares | – | Dec 31, 2024 | SEC |
| Jan 10, 202511:55 AM ET | Conestoga Capital Advisors, LLCand 1 other | 13G/A | 11.38%618.1K shares | – | Dec 31, 2024 | SEC |
Form 144: proposed insider sales
Notices from officers, directors and other affiliates planning to sell Mesa Laboratories Inc shares.
No Form 144 notices for Mesa Laboratories Inc are on file.