SAN FRANCISCO — Some high-profile general counsel in San Francisco and Silicon Valley have gone back to law firms in recent months. In an industry where books of business are paramount, some industry observers question whether the money firms spend on these former GCs would be better spent on nabbing a rainmaker on the lateral market. But the firms say the former GCs have unique qualities that are worth paying for.

In early June, Sheppard, Mullin, Richter & Hampton announced it had hired former Broadcom Corp. general counsel Arthur Chong as a special adviser in San Francisco. Less than two weeks later, Cooley picked up former eBay Inc. general counsel Michael Jacobson as of counsel in Palo Alto. And almost a year ago, Goodwin Procter hired William Growney, the former GC of RichRelevance Inc. and Napster Inc., as a partner in Menlo Park.