IONS Ionis Pharmaceuticals, Inc.

NASDAQ
$51.44

Ionis Pharmaceuticals, Inc. (IONS) 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 Subdued Selling ran below IONS's own trailing one-year pace, with 97% of sale value under a prearranged plan.
Cluster activity 0 buyers in the last 30 days 1 buyer in the last 90 days 9 sellers in the last 90 days
Insiders buying
1
2 transactions
Insiders selling
15
33 transactions
Purchases
$1.1M
20,000 shares
Sales
$30.5M
394,698 shares
Net activity
-$29.4M
purchases less sales

How much of that selling was preplanned? 97% planned / 3% discretionary

10b5-1 plan sales $29.6M 30 transactions · 383,204 shares
Discretionary sales $860.5K 3 transactions · 11,494 shares

Largest single sale: $4.5M.

Where they traded

Buy Sell Dot area is proportional to transaction value.

Last open-market purchase: July 31, 2026 , by Hayden Michael R .

Recent open-market activity

Date Insider Role Action Shares Price Value Held after
Hayden Michael R Director Buy 5,000 $51.60 $258.0K 24,000
Hayden Michael R Director Buy 15,000 $53.38 $800.7K 19,000
BENNETT C FRANK 2 fills EVP, Chief Scientific Officer Sell 10b5-1 20,536 $84.95 $1.7M 75,018 −21.5% of holding
Diaz Allene M. Director Sell 10b5-1 10,111 $85.42 $863.6K 3,811 −72.6% of holding
Kordasiewicz Holly B. EVP, Chief Development Officer Sell 10b5-1 362 $84.30 $30.5K 22,096 −1.6% of holding
KLEIN JOSEPH III 2 fills Director Sell 10b5-1 11,518 $79.04 $910.4K 22,433 −33.9% of holding
Monia Brett P Chief Executive Officer Sell 10b5-1 50,000 $80.59 $4.0M 245,571 −16.9% of holding
Schneider Eugene EVP, Chf Clinical Develop Ofcr Sell 10b5-1 26,000 $81.05 $2.1M 77,114 −25.2% of holding
Baroldi Joseph EVP, Chief Business Officer Sell 10b5-1 5,635 $80.16 $451.7K 4,669 −54.7% of holding
O'NEIL PATRICK R. EVP CLO & General Counsel Sell 10b5-1 3,069 $80.00 $245.5K 61,470 −4.8% of holding
Monia Brett P Chief Executive Officer Sell 10b5-1 21,072 $78.49 $1.7M 245,571 −7.9% of holding
Swayze Eric EVP Research Sell 10b5-1 10,602 $79.18 $839.5K 21,759 −32.8% of holding
Monia Brett P Chief Executive Officer Sell 10b5-1 14,565 $78.41 $1.1M 245,571 −5.6% of holding
BERTHELSEN SPENCER R Director Sell 10b5-1 8,000 $73.49 $587.9K 156,013 −4.9% of holding
Kordasiewicz Holly B. 2 fills EVP, Chief Development Officer Sell 10b5-1 60,846 $73.41 $4.5M 42,300 −59% of holding
BERTHELSEN SPENCER R Director Sell 10b5-1 8,000 $75.67 $605.4K 156,013 −4.9% of holding
Monia Brett P Chief Executive Officer Sell 10b5-1 3,220 $78.68 $253.3K 242,662 −1.3% of holding
Monia Brett P Chief Executive Officer Sell 10b5-1 1,316 $78.01 $102.7K 242,662 −0.5% of holding
LOSCALZO JOSEPH 2 fills Director Sell 10b5-1 77,289 $75.06 $5.8M 54,111 −58.8% of holding
KLEIN JOSEPH III 2 fills Director Sell 10b5-1 10,111 $73.51 $743.2K 12,445 −44.8% of holding
Baroldi Joseph EVP, Chief Business Officer Sell 10b5-1 1,626 $71.79 $116.7K 44,909 −3.5% of holding
Baroldi Joseph EVP, Chief Business Officer Sell 5,619 $74.56 $419.0K 46,535 −10.8% of holding
Jenne Kyle EVP, Chf GL Pdt Str Ofcr Sell 4,902 $75.17 $368.5K 23,713 −17.1% of holding
Birchler Brian EVP, Corp and Development Ops Sell 973 $75.04 $73.0K 67,500 −1.4% of holding
PARSHALL B LYNNE 2 fills Director Sell 10b5-1 5,000 $76.27 $381.4K 51,878 −8.8% of holding
Devers Shannon L. EVP, Chief Human Resources Ofc Sell 10b5-1 6,193 $74.05 $458.6K 16,348 −27.5% of holding
KLEIN JOSEPH III 2 fills Director Sell 10b5-1 22,321 $75.55 $1.7M 13,230 −62.8% of holding
Schneider Eugene EVP, Chf Clinical Develop Ofcr Sell 10b5-1 5,812 $70.97 $412.5K 63,890 −8.3% of holding

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.