What happened 

Shares of Arista Networks (ANET 0.64%), a cloud networking provider, were tumbling today after the company reported its first-quarter financial results. Surprisingly, the tech stock was falling despite beating analysts' top- and bottom-line consensus estimates. 

Investors instead focused their attention on the fact that Arista's management said that spending from some of its biggest customers could slow down. That sent the stock down by 14.9% as of 12:34 p.m. ET. 

So what 

Arista reported non-GAAP (adjusted) earnings per share of $1.43 for the first quarter, which was up from $0.84 in the year-ago quarter and ahead of Wall Street's average estimate of $1.34.

Additionally, the company's first-quarter sales soared 54% to $1.35 billion, outpacing analysts' consensus estimate of $1.31 billion. Usually, when a company beats Wall Street's top- and bottom-line estimates in a quarter, its share price jumps. But investors looked past Arista's results today and instead focused their attention on management's earnings call comments. 

In particular, Arista's CFO Ita Brennan said on the call that the company expects "some moderation in customer spending, especially with our cloud titan customers following a year of accelerated demand in 2022." 

As Barron's pointed out today, the "titans" that Brennan is referring to are likely Microsoft and Meta, which account for 16% and 26% of the company's sales, respectively. 

Now what 

While investors are right to be concerned about any potential slowdown in spending from some of Arista's largest customers, they may also want to consider that Arista still had a good quarter and has lots of long-term potential in huge markets, including artificial intelligence.