How Much Does Arista Networks Stock Move When The Market Moves

Arista Networks (ANET) has gained 5.6% over the last five trading days while the S&P 500 added 0.6%. A gap like that pulls buyers in. But the five-day move is not the question. The real one is what owning Arista does to your money every time the market moves, because it travels much further than the index in both directions.

Arista Has Moved Twice As Far As The Market In Both Directions

Arista cushions nothing. On days the S&P 500 rose over the past year, it captured about 212% of the market's gain. On days the index fell, it absorbed about 212% of the market's loss.

That is a one-year reading on daily moves, and it can change. Over the past five years, Arista ran 48.8% annualized volatility against 17.2% for the S&P 500, close to three times the index's swing. That five-year figure covers all days and runs wider than the one-year capture.

Correlation is a different measure. Over those same five years, Arista's daily moves tracked the index at 0.56, so it shares some of the market's direction and keeps behavior of its own. Direction is not the problem. Distance is.

So What Is Arista Levered To?

A small set of very large buyers. Arista sells AI fabrics built on Etherlink switches, and management names Microsoft and Meta as its two longest-standing partners. Arista expects one or two customers to each take at least a tenth of revenue.

The parts come from somewhere else. Management has almost tripled its multiyear purchase commitments over the past year, to about $9.7 billion at the end of fiscal Q2 2026. Even so, the CEO says the industry does not get clear of its supply shortage until 2028.

So the swing has a source. Demand sits with a very small number of customers, supply sits with an industry shortage Arista does not control, and the stock trades at 62.2 times earnings against an S&P 500 median of 22.5. None of that is a flaw. It is what a direct bet on AI build-out looks like.

Have You Been Paid For The Swing?

So far, yes. Over the past five years, Arista returned 54.8% a year against 13.1% for the S&P 500. Adjusted for risk the edge is much smaller: a five-year Sharpe ratio of 1.07 against 0.57, which measures return above the risk-free rate for each unit of swing. The next stretch depends on whether demand keeps turning into shipments.

Management raised its 2026 revenue guidance for the third time, to $12.6 billion and 40% annual growth. That added $1.1 billion to its May 2026 projection, and management has not split it by product line. It expects every product line to contribute, and says the mix depends on what it can ship.

Arista keeps enough behavior of its own to earn a place on its own merits, and over five years it has paid well for the ride. What it will not do is soften the market's bad days. What ships from here tells you whether that trade stays worth making.

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