MLAB Mesa Laboratories, Inc.

NASDAQ
$129.30

Mesa Laboratories, Inc. (MLAB) Insider Activity

What the officers, directors and large holders did with their own shares. Only open-market purchases and sales count toward the totals — grants, option exercises and shares withheld for tax are compensation mechanics, not decisions, and they're listed separately below.

Insider signal Bullish Insiders bought more than they sold over this window — uncommon at any size.
Cluster activity 0 buyers in the last 30 days 2 buyers in the last 90 days 1 seller in the last 90 days
Insiders buying
2
2 transactions
Insiders selling
1
1 transaction
Purchases
$902.4K
7,993 shares
Sales
$800.1K
7,093 shares
Net activity
$102.3K
purchases less sales

How much of that selling was preplanned? 0% planned / 100% discretionary

10b5-1 plan sales $0 0 transactions · 0 shares
Discretionary sales $800.1K 1 transaction · 7,093 shares

Largest single sale: $800.1K.

Where they traded

Buy Sell Dot area is proportional to transaction value.

Last open-market purchase: August 13, 2026 , by Tripeny R Tony .

Recent open-market activity

Date Insider Role Action Shares Price Value Held after
Sullivan John James Director Sell 7,093 $112.80 $800.1K 17,834 −28.5% of holding
Kadia Siddhartha President and CEO Buy 7,093 $112.80 $800.1K 7,093
Tripeny R Tony Director Buy 900 $113.69 $102.3K 6,298

Form 4s are due within two business days of a transaction, so this is close to real time — unlike the quarterly 13F data on the Institutional tab. A single large sale often reflects a prearranged 10b5-1 plan rather than a fresh view, so read a pattern of sales rather than any one of them.