Some are predicting that investors will gobble up the stock. Dow Jones says it's expected to price the stock at $43, well above its initial $36-$40 range.
Investors probably like the fact that Arista is already profitable and growing nicely. Revenues nearly doubled from $193.4 million in 2012 to $361.2 million in 2013, and in that same time profits doubled, too, from $21.4 million to $42.5 million.
Plus, Arista has some huge customers, and it plays in a hot market, corporate computer network equipment, an area that is undergoing a lot of change. That change has been good for Arista, whose CEO, Jayshree Ullal, was one of the top engineers at the rival Cisco, before Arista lured her away.
However, the company is also embroiled in a double dose of controversy: an odd lawsuit by one of its co-founders and accusations of offering stock to journalists.
Arista was founded by billionaires and close friends David Cheriton and Andy Bechtolsheim, who famously provided seed money to Google in 1998. (The story goes: they viewed a demo of a project from two graduate students, Larry Page and Sergey Brin, and promptly each cut a check for $100,000.)
Bechtolsheim is perhaps best known as a co-founder of Sun who went on to fund a lot of other successful tech companies. Cheriton is known as "Professor Billionaire," is tenured at Stanford, and has taught and advised countless tech bigwigs.
They self-funded Arista, their third company together.
But buried in the IPO paperwork, Arista revealed that Cheriton had left the company in March and that another startup he founded, OptumSoft, was threatending to sue. In April, the suit was filed.
And here's the weird thing, Cheriton is Arista's largest shareholder.
"In a way, he's suing himself. I've never seen that before," University of Houston law professor Ray Nimmer told Forbes' Ryan Mac and Alex Konrad.
In the early days OptumSoft and Arista were sister companies, sharing an office and working closely together, reports Forbes.
The two don't disagree on this part: Arista used OptumSoft's software to create Arista's products. The dispute centers on what parts of Arista's software OptumSoft can now lay claim to because of that.
If the outcome of the lawsuit gives OptumSoft rights to a lot of Arista's software, then Arista could be in deep trouble. OptumSoft's business model is to license software to many companies. That means it could license Arista's secret sauce to its competitors, giving away Arista's competitive advantage.
Given Cheriton's relationship to Arista, this suit may be about something other than money.
OptumSoft didn't flourish as Arista did (it has 25 employees to Arista's 850+). Over time, Cheriton's influence at Arista waned as he was able to devote limited time to it while meeting his obligations at Stanford, Forbes reports.
Meanwhile OptumSoft represents a labor of love for Cheriton, the culmination of a lifetime of research on how to build large cloud computer systems. He has a big personal commitment to it. It may be more important to him to take a stand on a situation he thinks is unfair to OptumSoft, even though that stand could hurt the IPO and his own pocketbook.
Or he could be holding out for a bigger settlement from Arista.
In between all of this Arista suffered another controversy. It came under fire about a month ago when tech journalist Adam Lashinsky revealed that Arista offered him pre-IPO shares of the stock. In other words, Arista was trying to bribe him and other tech journalists, as our own Henry Blodget described it.
So, like we said, Arista's IPO will be interesting to watch.
We've reached out to OptumSoft for comment. Arista tells us it is still in its quiet period and cannot comment.