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TNDM · Tandem Diabetes Care Inc

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Market Cap
$1.42B
Shares
69.58M

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

Holders: 275
Total Value: $1,282,785,591
Total Shares: 85,009,088
Showing 1–100 of 288 holdings by value · page 1 of 3

Institutional Ownership Trend

26 quarters

Holder Concentration

Across 275 13F filers · Δ vs Mar 31, 2026
Top Holder
13.6%
Sep 2023 → Jun 2026 · range 11.9% – 15.5%
+1.0 pts
Top 5
36.1%
Sep 2023 → Jun 2026 · range 33.5% – 44.0%
+0.9 pts
Top 10
51.2%
Sep 2023 → Jun 2026 · range 48.5% – 58.8%
+0.7 pts
HHI
414
Sep 2023 → Jun 2026 · range 374 – 514
Broadly held+11

Quarterly Activity

vs Mar 31, 2026
New
48
Increased
97
Decreased
91
Sold Out
50
Unchanged
39
Holder count: -2
Institutional value: -20.8%
Shares held: +0.6%

Top Buyers

vs Mar 31, 2026
Institution Added Now Holds Open

Top Sellers

vs Mar 31, 2026
Institution Sold Now Holds Open

Top New Positions

vs Mar 31, 2026
Institution Acquired Value (USD) Open

Top Sold-Out Positions

vs Mar 31, 2026
Institution Previously Held Last Value (USD) Open
Showing 100 of 288
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Holder Value (USD) % of 13F Shares Open
Key facts CIK 1438133 CUSIP 875372203 13F (30d) 202 filings 199 filers Visit website Investor relations