Peter Fenton

Peter Fenton, a partner at Accel Partners has defected and is joining another big-name Silicon Valley venture capital firm, Benchmark Capital.

We’re hearing the matter is so sensitive the Benchmark folks aren’t taking calls about it. Benchmark has put out a release (download here), which hits the wires tomorrow. We put in a call to Accel’s leading partner, Jim Breyer, but he was in a meeting offsite, so we couldn’t run it by him.

Fenton, 33, led and managed Accel’s investments in more than ten companies, including the successful acquisitions of JBoss and Wily Technology. “He is a superstar,” said Kevin Harvey, general partner at Benchmark Capital, in a statement. It is not yet clear what will happen with Fenton’s board seats.

These sorts of defections of partners at top-tier firms are unusual, in part because they are usually intimately tied in deep relationships within their respective firms. Internecine struggles are frowned upon by the large institutional investors, who entrust their money to the venture capital firms; they cherish stability.

At most firms, partners vote together when to invest in a company, and a partner who takes a company board is responsible for overseeing the firm’s investment at that company. If he leaves, he creates all kinds of complications, not only about what to do with the firm’s board seats at companies it has backed, but also about how to dissolve the partner’s percentage ownership within the firm. Lawyers get involved, and it can be acrimonious. You will see associates and lower level folks move all the time, but not partners.

The departure is fresh, because Fenton is still listed on Accel’s site, as of this posting at least. (Update: As of Thursday morning, we see Fenton’s bio has gone)

This comes two years after another Accel partner, Jim Goetz left the firm to join another top-notch Silicon Valley firm, Sequoia Capital.

Granted, this doesn’t necessarily mean there is anything wrong at Accel. Sequoia and Benchmark are known as the most aggressive firms in Silicon Valley, so this may be more a question of poaching than any serious dissatisfaction with the Breyer’s compensation structure — but truth is, we don’t know.