Tandem Diabetes Care, Inc.
MX ˙ BMV ˙ US8753722037
SecurityMX:TNDM / Tandem Diabetes Care, Inc.
InstitutionNatixis Advisors, L.p.
Latest Disclosed Ownership61,084 shares
Latest Disclosed Value $ 1,171
Natixis Advisors, L.p. reports 7.13% increase in ownership of TNDM / Tandem Diabetes Care, Inc.

On May 13, 2026 - Natixis Advisors, L.p. filed a 13F-HR form disclosing ownership of 61,084 shares of Tandem Diabetes Care, Inc. (MX:TNDM) valued at $1,171 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 57,021 shares of Tandem Diabetes Care, Inc.. This represents a change in shares of 7.13% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-13 2026-03-31 13F TANDEM DIABETES CARE COM 875372203 61,084 4,063 7.13 1 0.00 0.0016
2026-02-10 2025-12-31 13F TANDEM DIABETES CARE COM 875372203 57,021 617 1.09 1 0.0018
2025-11-13 2025-09-30 13F TANDEM DIABETES CARE INC COM 875372203 56,404 13,992 32.99 1 0.0010
2025-08-13 2025-06-30 13F TANDEM DIABETES CARE COM 875372203 42,412 -23,161 -35.32 1 -100.00 0.0013
2025-05-08 2025-03-31 13F TANDEM DIABETES CARE COM 875372203 65,573 -105 -0.16 1 -50.00 0.0023
2025-02-10 2024-12-31 13F TANDEM DIABETES CARE COM 875372203 65,678 1,972 3.10 2 0.00 0.0044
2024-11-06 2024-09-30 13F TANDEM DIABETES CARE COM 875372203 63,706 10,462 19.65 3 0.00 0.0053
2024-08-01 2024-06-30 13F TANDEM DIABETES CARE COM 875372203 53,244 3,034 6.04 2 100.00 0.0047
2024-04-25 2024-03-31 13F TANDEM DIABETES CARE COM 875372203 50,210 15,529 44.78 2 0.00 0.0041
2024-02-06 2023-12-31 13F TANDEM DIABETES CARE COM 875372203 34,681 34,681 1 0.0027
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.