The Two Who Swapped PlacesThin moat
Arista Networks (ANET) — moat facet
One went 21% to 16%, the other 18% to 26% — a single deployment decision moves several points of Arista's revenue.
Arista's 10-K gives three years of figures for both of its largest customers, and read together they describe a reordering. One end customer was 21% of total revenue in 2023, 15% in 2024 and 16% in 2025. The other was 18%, then 20%, then 26%.
The combined number moved much less than either component: 39%, 35%, 42%. An investor watching only the total would have seen a dip and a recovery, and missed that Arista's dependence had migrated from one buyer to another — one whose spending fell by a quarter and one whose spending grew by nearly half over the same period.
That volatility is the honest character of this customer base. These are companies building data centres on multi-year capital plans that get revised, and a single deployment decision moves several points of Arista's revenue. The risk factors are explicit about the unpredictability in the timing and volume of large customer orders1.
Watch both percentages separately rather than the sum. The sum tells you how concentrated Arista is; the components tell you whether the concentration is stable — and a customer moving five points in a year in either direction is the more useful early warning.
One customer fell from 21% to 16% of revenue while the other rose from 18% to 26%, and the combined figure reached 42%. Both the level and the volatility worsened. These are companies making independent multi-year capital decisions that Arista absorbs, and the filing is explicit about the unpredictability of large-customer order timing.
One end customer went 21% to 15% to 16% of revenue; the other 18% to 20% to 26%. Arista's filing notes unpredictability in the timing and volume of large customer orders. Watch the components rather than the sum.
Source: Arista Form 10-K, FY2025 ↗- ReportedOne end customer was 21%, 15% and 16% of total revenue across 2023-2025 while the other was 18%, 20% and 26%; the filing notes unpredictability in the timing and volume of large customer orders.Arista Networks Form 10-K, FY2025 — two customers accounted for more than 10% of total revenue in each of the last three years; sales to one end customer represented 16%, 15% and 21% of total revenue and sales to the other end customer represented 26%, 20% and 18% of total revenue for the years ended December 31, 2025, 2024 and 2023 respectively; the company notes unpredictability in the timing and volume of large customer orders, that large customers may receive lower pricing terms due to volume discounts or may elect to re-assign allocations to multiple vendors based upon specific requirements, and that it continues to diversify its enterprise customers across media and entertainment, healthcare, oil and gas, education, manufacturing and industrial sectors — FY2025 (ended December 31, 2025) · publ. February 17, 2026 · source ↗