A10 Networks, Inc.
US ˙ NYSE ˙ US0021211018

SecurityATEN / A10 Networks, Inc.
InstitutionSei Investments Co
Latest Disclosed Ownership123,356 shares
Latest Disclosed Value $ 2,182,154
Sei Investments Co reports 2.30% decrease in ownership of ATEN / A10 Networks, Inc.

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 123,356 shares of A10 Networks, Inc. (US:ATEN) valued at $2,182,168 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 126,266 shares of A10 Networks, Inc.. This represents a change in shares of -2.30% during the quarter. The current value of the position is $3,770,993 USD.

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)
2026-02-13 2025-12-31 13F A10 NETWORKS COM 002121101 123,356 -2,910 -2.30 2,182 -4.76 0.0022
2025-11-13 2025-09-30 13F A10 NETWORKS COM 002121101 126,266 -59,927 -32.19 2,292 -36.40 0.0025
2025-08-14 2025-06-30 13F A10 NETWORKS COM 002121101 186,193 -35,030 -15.83 3,603 -0.33 0.0042
2025-05-14 2025-03-31 13F/A-1 A10 NETWORKS COM 002121101 221,223 26,187 13.43 3,615 0.72 0.0047
2025-05-13 2025-03-31 13F A10 NETWORKS COM 002121101 220,595 25,559 4,006 0.0044
2025-02-11 2024-12-31 13F A10 NETWORKS COM 002121101 195,036 -24,390 -11.12 3,589 13.26 0.0046
2024-11-12 2024-09-30 13F A10 NETWORKS COM 002121101 219,426 9,315 4.43 3,169 8.87 0.0041
2024-08-13 2024-06-30 13F A10 NETWORKS COM 002121101 210,111 987 0.47 2,910 1.68 0.0041
2024-05-07 2024-03-31 13F A10 NETWORKS COM 002121101 209,124 -4,351 -2.04 2,863 1.81 0.0042
2024-02-14 2023-12-31 13F A10 NETWORKS COM 002121101 213,475 -9,959 -4.46 2,811 -16.29 0.0045
2023-11-14 2023-09-30 13F A10 NETWORKS COM 002121101 223,434 -20,583 -8.44 3,358 -5.67 0.0060
2023-08-11 2023-06-30 13F A10 NETWORKS COM 002121101 244,017 -9,995 -3.93 3,560 -9.51 0.0062
2023-05-12 2023-03-31 13F A10 NETWORKS COM 002121101 254,012 -62,274 -19.69 3,935 -25.19 0.0073
2023-02-10 2022-12-31 13F A10 NETWORKS COM 002121101 316,286 15,033 4.99 5,260 31.57 0.0117
2022-11-14 2022-09-30 13F A10 NETWORKS COM 002121101 301,253 -29,061 -8.80 3,997 -15.85 0.0089
2022-08-15 2022-06-30 13F A10 NETWORKS COM 002121101 330,314 -50,054 -13.16 4,750 -10.28 0.0103
2022-05-13 2022-03-31 13F A10 NETWORKS COM 002121101 380,368 -15,830 -4.00 5,294 -19.34 0.0106
2022-02-14 2021-12-31 13F A10 NETWORKS COM 002121101 396,198 296,599 297.79 6,563 388.68 0.0123
2021-11-12 2021-09-30 13F A10 NETWORKS COM 002121101 99,599 85,120 587.89 1,343 723.93 0.0028
2021-08-06 2021-06-30 13F A10 NETWORKS COM 002121101 14,479 -1,448 -9.09 163 4.49 0.0004
2021-05-12 2021-03-31 13F A10 NETWORKS COM 002121101 15,927 4,145 35.18 156 34.48 0.0004
2021-02-08 2020-12-31 13F A10 NETWORKS COM 002121101 11,782 11,782 116 0.0003
2019-05-15 2019-03-31 13F A10 NETWORKS COM 002121101 0 -7,331 -100.00 0 -100.00
2019-02-13 2018-12-31 13F A10 NETWORKS COM 002121101 7,331 7,331 46 0.0002
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.