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Company profile

Tandem Diabetes Care Inc Insider Trading

TNDM

Every SEC Form 4 insider trading filing for Tandem Diabetes Care Inc (TNDM) since April 2023 — open-market buys and sells by directors and officers, option exercises, and cluster activity, updated as each filing is reported to the SEC. Why 2023?

Exchange
Nasdaq
Sector
Surgical & Medical Instruments & Apparatus
CIK
0001438133
Filings
250
Insiders
21
Last filing
2026-08-15
SEC EDGAR ↗Yahoo Finance ↗Finviz ↗Stock Analysis ↗

Activity summary

No insider transactions in the last 30 days. The most recent was on August 15, 2026, when John F Sheridan sold 5,055 shares. 250 filings from 21 insiders are on record below.

Three year balance

Buy and sell value by quarter, Q4 23 to Q3 26. Tandem Diabetes Care Inc insiders are net sellers across the period shown.

PurchasesSales
Q4 23Q1 24$2.3MQ2 24Q3 24Q4 24Q1 25Q2 25Q3 25Q4 25Q1 26Q2 26Q3 26

Bars below the rule are sales, above are purchases. Largest quarter on the chart is $2.3M.

90 day insight

Over the last 90 days, Tandem Diabetes Care Inc insiders bought $0 (28 transactions) and sold $378K (14 transactions).

  • Most active insider: John F Sheridan with 6 transactions totaling $184K.
  • Largest single sale: $115K by John F Sheridan on Aug 15, 2026.

Activity skews bullish — buys outpace sales.

Insider Transactions

Sourced from SEC EDGAR Form 4 filings. Updated hourly.

DateInsiderCompanyTypeSharesPriceValueReturn
Aug 15, 2026John F SheridanTNDM
Tax Withholding
5,055$22.72$115K-24.8% 1m
Aug 15, 2026Elizabeth Anne GasserTNDM
Option Exercise
1,097——-24.8% 1m
Aug 15, 2026Leigh VossellerTNDM
Tax Withholding
942$22.72$21K-24.8% 1m
Aug 15, 2026Leigh VossellerTNDM
Option Exercise
2,624——-24.8% 1m
Aug 15, 2026John F SheridanTNDM
Option Exercise
5,982——-24.8% 1m

45 more transactions hidden

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Top insiders

By total value filed.

John F SheridanPRESIDENT & CEO2 filings−$184K
Jean-Claude KyrillosEVP & Chief Operating Officer2 filings−$42K
Elizabeth Anne GasserEVP, Chief Strategy Officer2 filings−$37K
Shannon Marie HansenEVP & Chief Legal Officer2 filings−$35K
Leigh VossellerEVP & CHIEF FINANCIAL OFFICER2 filings−$34K

Institutional Ownership

Top 13F-HR holders of Tandem Diabetes Care Inc as of 2026-06-30

↓ decreasing
Total reported AUM
$344.8M
QoQ change
-76.1%
Reporting period
2026-06-30
#1
BlackRock, Inc.
CIK 0002012383
$116.3M
7.7M shares
#2
State Street Corp
CIK 0000093751
$43.0M
2.9M shares
#3
BlackRock, Inc.
CIK 0002012383
$36.8M
2.4M shares

Data source: quarterly 13F-HR filings — institutional holders report positions within 45 days of quarter end. Joined with insider activity above — see who's loading up institutionally while insiders are trading. Full 13F-HR API →

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Form4API, StockholmNot affiliated with the SEC or EDGAR. Data sourced from public EDGAR filings. Not investment advice.

Congressional Trading

Disclosed TNDM trades under the STOCK Act

Total trades
4
Purchases
3
Sales
1
Gilbert Ray Cisneros, Jr.
Democrat · House · CA
2 buys
0 sells
Josh Gottheimer
Democrat · House · NJ
1 buy
1 sell

Sourced from U.S. House Clerk periodic transaction reports (House coverage only). Trade counts reflect disclosed filings only. The STOCK Act allows up to 45 days between a trade and its disclosure, so this reflects recent disclosures, not real-time trading. Full congressional trading API →

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