Arista Networks, Inc.
MX ˙ BMV ˙ US0404132054
SecurityMX:ANET / Arista Networks, Inc.
InstitutionBlair William & Co/il
Latest Disclosed Ownership1,151,227 shares
Latest Disclosed Value $ 141,347,604
Blair William & Co/il reports 2.37% increase in ownership of ANET / Arista Networks, Inc.

On May 8, 2026 - Blair William & Co/il filed a 13F-HR form disclosing ownership of 1,151,227 shares of Arista Networks, Inc. (MX:ANET) valued at $141,347,604 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 1,124,560 shares of Arista Networks, Inc.. This represents a change in shares of 2.37% 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)
2026-05-08 2026-03-31 13F ARISTA NETWORKS COM SHS 040413205 1,151,227 26,667 2.37 141,348 -4.07 0.4051
2026-02-17 2025-12-31 13F ARISTA NETWORKS COM SHS 040413205 1,124,560 11,992 1.08 147,351 -9.11 0.3955
2025-11-12 2025-09-30 13F ARISTA NETWORKS COM SHS 040413205 1,112,568 -44,814 -3.87 162,112 36.91 0.4315
2025-07-24 2025-06-30 13F ARISTA NETWORKS COM SHS 040413205 1,157,382 125,362 12.15 118,412 48.09 0.3289
2025-05-09 2025-03-31 13F ARISTA NETWORKS COM SHS 040413205 1,032,020 194,868 23.28 79,961 -13.58 0.2412
2025-02-12 2024-12-31 13F ARISTA NETWORKS COM SHS 040413205 837,152 623,990 292.73 92,530 13.10 0.2692
2024-11-12 2024-09-30 13F ARISTA NETWORKS COM 040413106 213,162 -2,880 -1.33 81,816 8.05 0.2403
2024-08-12 2024-06-30 13F ARISTA NETWORKS COM 040413106 216,042 7,922 3.81 75,718 25.46 0.2335
2024-05-09 2024-03-31 13F ARISTA NETWORKS COM 040413106 208,120 -3,350 -1.58 60,351 21.18 0.1896
2024-02-12 2023-12-31 13F ARISTA NETWORKS COM 040413106 211,470 -1,432 -0.67 49,803 27.18 0.1697
2023-11-09 2023-09-30 13F ARISTA NETWORKS COM 040413106 212,902 1,220 0.58 39,159 14.15 0.1502
2023-08-11 2023-06-30 13F ARISTA NETWORKS COM 040413106 211,682 5,634 2.73 34,305 -0.82 0.1257
2023-05-12 2023-03-31 13F ARISTA NETWORKS COM 040413106 206,048 -1,495 -0.72 34,587 37.33 0.1382
2023-02-10 2022-12-31 13F ARISTA NETWORKS COM 040413106 207,543 -2,518 -1.20 25,185 6.20 0.1095
2022-11-09 2022-09-30 13F ARISTA NETWORKS COM 040413106 210,061 -18,966 -8.28 23,714 10.46 0.1089
2022-08-10 2022-06-30 13F ARISTA NETWORKS COM 040413106 229,027 -320,311 -58.31 21,469 -71.88 0.0952
2022-05-13 2022-03-31 13F ARISTA NETWORKS COM 040413106 549,338 2,726 0.50 76,347 -2.84 0.2676
2022-02-14 2021-12-31 13F ARISTA NETWORKS COM 040413106 546,612 407,913 294.10 78,575 64.86 0.2464
2021-11-12 2021-09-30 13F ARISTA NETWORKS COM 040413106 138,699 79 0.06 47,663 -5.10 0.1622
2021-08-12 2021-06-30 13F ARISTA NETWORKS COM 040413106 138,620 4,835 3.61 50,223 24.35 0.1740
2021-05-13 2021-03-31 13F ARISTA NETWORKS COM 040413106 133,785 -164 -0.12 40,388 3.77 0.1524
2021-02-09 2020-12-31 13F ARISTA NETWORKS COM 040413106 133,949 15,767 13.34 38,922 59.16 0.1427
2020-11-06 2020-09-30 13F ARISTA NETWORKS COM 040413106 118,182 -142,964 -54.74 24,455 -55.41 0.1037
2020-08-12 2020-06-30 13F ARISTA NETWORKS COM 040413106 261,146 13,206 5.33 54,848 9.22 0.2615
2020-05-11 2020-03-31 13F ARISTA NETWORKS COM 040413106 247,940 16,756 7.25 50,220 6.80 0.3139
2020-02-13 2019-12-31 13F ARISTA NETWORKS COM 040413106 231,184 114,125 97.49 47,023 68.13 0.2417
2019-11-12 2019-09-30 13F ARISTA NETWORKS COM 040413106 117,059 25,238 27.49 27,968 17.32 0.1612
2019-08-13 2019-06-30 13F ARISTA NETWORKS COM 040413106 91,821 23,053 33.52 23,839 10.24 0.1363
2019-05-14 2019-03-31 13F ARISTA NETWORKS COM 040413106 68,768 10,783 18.60 21,625 77.01 0.1318
2019-02-14 2018-12-31 13F ARISTA NETWORKS COM 040413106 57,985 33,819 139.94 12,217 90.15 0.0892
2018-11-13 2018-09-30 13F ARISTA NETWORKS COM 040413106 24,166 1,630 7.23 6,425 10.72 0.0394
2018-08-13 2018-06-30 13F ARISTA NETWORKS COM 040413106 22,536 -514 -2.23 5,803 -1.39 0.0395
2018-05-15 2018-03-31 13F ARISTA NETWORKS COM 040413106 23,050 11,754 104.05 5,885 121.16 0.0416
2018-02-14 2017-12-31 13F ARISTA NETWORKS COM 040413106 11,296 -9,579 -45.89 2,661 -32.77 0.0181
2017-11-13 2017-09-30 13F ARISTA NETWORKS COM 040413106 20,875 13,395 179.08 3,958 253.39 0.0297
2017-08-04 2017-06-30 13F ARISTA NETWORKS COM 040413106 7,480 2,304 44.51 1,120 65.19 0.0084
2017-05-10 2017-03-31 13F ARISTA NETWORKS COM 040413106 5,176 291 5.96 678 43.34 0.0055
2017-02-14 2016-12-31 13F ARISTA NETWORKS COM 040413106 4,885 2,385 95.40 473 122.07 0.0042
2016-11-14 2016-09-30 13F ARISTA NETWORKS COM 040413106 2,500 2,500 213 0.0019
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.