A worker oversees a vibratory conveyer at a Roche packaging facility.
A worker oversees a vibratory conveyer at a Roche packaging facility. (Christopher Gmuender/Roche)

Correction, 8/8/14, 4:46 p.m.: An earlier version of this story misidentified the law firm representing GoPro on its initial public offer. Fenwick & West advised GoPro while Wilson Sonsini Goodrich & Rosati counseled the underwriters. The story has been updated accordingly. We regret the error.

Swiss drug giant Roche Holdings has agreed to pay up to $1.7 billion to buy Seragon Pharmaceuticals, a San Diego-based maker of breast cancer treatments being advised by Wilson Sonsini Goodrich & Rosati, which is also counseling online vitamin seller Vitacost.com on its $280 million sale to supermarket chain The Kroger Co.

Advising on sale of the two companies could mark the beginning of another busy quarter for Wilson Sonsini, which just capped an active second quarter that included the firm counseling data storage provider Fusion-io on its proposed $1.1 billion sale to SanDisk Corp., as recently reported by sibling publication The Recorder. Wilson Sonsini recently represented Google’s Nest unit on its $555 million acquisition of home-monitoring camera startup Dropcam.

The Silicon Valley stalwart also took the lead for high-speed computer networking maker Arista Networks on its $226 million initial public offering, as well as advised the underwriters on the $427 million float last month by wearable action camera maker GoPro. Fenwick & West represented GoPro. (SEC filings show that GoPro’s listing yielded $2.35 million in legal fees and expenses, while Arista generated another $2 million.)

Shepherding the sale of Seragon for Wilson Sonsini are corporate partners Kenneth Clark and Robert Ishii, IP partners Miranda Biven and Michael Hostetler and associate Chang “Derek” Liu.

Roche’s Genentech subsidiary has agreed to pay $725 million in cash for Seragon, plus an additional $1 billion if the biotech firm hits certain milestones for experimental cancer drugs that could take up to five years to come to market. Seragon was formed last year by scientists from Aragon Pharmaceuticals following the latter’s $650 million sale to Johnson & Johnson. Wilson Sonsini advised Aragon on that deal, and the firm also had a key role representing Genentech on its $46.8 billion sale to Roche five years ago.

Basel-based Roche, which earlier this month agreed to pay up to $350 million to acquire DNA sequencing company Genia Technologies, turned to Davis Polk & Wardwell for counsel on the Genentech deal. The firm has been a longtime standby for Roche transactional work, handling the company’s $230 million acquisition of Anadys Pharmaceuticals in 2011 and $450 million purchase earlier this year of medical testing equipment maker IQuum. (Roche also tapped Davis Polk to advise on its $6 billion takeover bid for San Diego-based Illumina in 2012, an effort that ultimately fell flat as Roche ended its pursuit of the gene-mapping equipment maker early last year.)

But a Davis Polk spokesman says that the firm does not have a role advising Roche on its proposed purchase of Seragon. Instead, Sidley Austin has snagged the Seragon work for Roche and its Genentech unit through M&A partner Sharon Flanagan and associate Aaron Rigby. Gottlieb Keller serves as Roche’s global general counsel, while Frederick “Rick” Kentz III is the drug giant’s chief compliance officer and North American head of legal affairs. Roche M&A counsel Ruben Perren and Genentech senior corporate counsel Grace Han McMahon have taken the lead in-house on the deal.

As for Wilson Sonsini, the firm is also representing Vitacost.com on the Boca Raton, Fla.-based online grocery and nutrition products retailer’s sale to Kroger, the nation’s largest supermarket operator. Corporate partners Robert Sanchez and Daniel Peale are leading a Wilson Sonsini team working on the matter that includes tax partner Ellen Marshall, employee benefits partner John Aguirre, IP and technology transactions partner James Clessuras, corporate of counsel Amy Simmerman and associates Barath Chari, Ryan Greecher, William Halliday, Rachel Landy, Michael Montfort and Kenisha Nicholson.

Vitacost.com raised $132 million through an initial public offering in 2009 that generated $700,000 in legal fees and expenses for lawyers from Chicago’s Shefsky & Froelich and Latham & Watkins, according to an SEC filing by the company at the time. (Ohio’s Taft Stettinius & Hollister merged with Shefsky & Froelich last year.) Mary Marbach now serves as chief legal officer for Vitacost.com.

Michael Aiello, chair of the corporate department at Weil, Gotshal & Manges, is leading a team from the firm advising Kroger that includes partner Matthew Gilroy, technology and IP transactions partner Michael Epstein, tax partner Kenneth Heitner, employee benefits partner Paul Wessel, privacy partner Randi Singer, environmental and climate change practice head Annemargaret Connolly, environmental counsel John O’Loughlin and associates Adrienne Baker, Cheri Bessellieu, Jennifer Britz, William Dong, Eoghan Keenan and Renee Pristas.

Weil and Aiello grabbed a role a year ago this month representing a financial adviser to Harris Teeter Supermarkets on its $2.4 billion sale to Cincinnati-based Kroger, according to our previous reports. That deal closed earlier this year.