UPDATE: 5/1/14, 1:28 p.m. EDT. The names of the lead lawyers from Wachtell advising Energizer have been added to the third paragraph of this story.

Four top Am Law 100 firms are handling corporate splits at Energizer Holdings and Alliant Techsystems.

St. Louis–based manufacturer Energizer Holdings announced plans Wednesday to divide into two publicly traded companies, one of which will focus on the Eveready and Energizer batteries made famous by its pink bunny icon and another specializing in consumer and personal care brands like the Edge and Schick shaving gels and Wet Ones antibacterial hand wipes. A press release put out by Energizer states that it has retained Wachtell, Lipton, Rosen & Katz and Bryan Cave to “advise on the separation process.”

Wachtell is no stranger to corporate breakups, having previously advised clients like ConocoPhillips, McGraw-Hill and Motorola on their separation plans. Corporate partners Steven Rosenblum and Steven Cohen, executive compensation and benefits partner Adam Shapiro and tax partner T. Eiko Stange are leading a team from the firm advising Energizer on its proposed split.

Bryan Cave has been a longtime legal adviser to Energizer. Former firm partner Mark LaVigne advised the company on its $1.9 billion acquisition of Playtex Products in 2007 and $275 million buy of Edge/Skintimate in 2009. LaVigne, who did not respond to a request for comment about Energizer’s separation, has served as the company’s general counsel since 2012 when he replaced the retiring Gayle Stratmann as in-house legal chief. (LaVigne first joined Energizer in 2010 as vice president and secretary.)

John Klein, who began his long business career as an associate at Sullivan & Cromwell, serves as an independent member of Energizer’s board of directors. The company hopes to complete its separation by the latter half of 2015.

U.S. Senate lobbying records show that Energizer paid $5,000 last year to former Holland & Knight partner Mary Ann Gilleece—now an attorney and managing director at Washington, D.C.’s Van Scoyoc Kelly PLLC—to lobby on issues “related to the development and improvement of batteries” being procured and acquired by the federal government.

On Tuesday, Arlington, Va.–based aerospace and defense contractor Alliant Techsystems announced that it would also effectively break up via the all-stock merger of its aerospace and defense units with satellite manufacturer Orbital Sciences Corp., while its consumer sporting goods division prepares to be spun off to existing shareholders.

Alliant general counsel Scott Chaplin—a former associate at Morgan, Lewis & Bockius and Reed Smith—and senior legal counsel and director of contracts Dianna Gibson are leading an in-house team advising the company on its split through a transaction structured under the tax-friendly Morris trust maneuver, as noted by The New York Times’ DealBook.

Cravath, Swaine & Moore M&A chair Philip Gelston and corporate partners Damien Zoubek, Craig Arcella and Stephen Kessing are leading a team from the firm representing Alliant in connection with the deal, which the company hopes to complete by year’s end. The Am Law Daily reported late last year on Cravath’s role advising Alliant on its $985 million purchase of sports eyewear company Bushnell Group Holdings—a maker of eyesights and telescopic lenses used in high-powered rifles—from private equity firm MidOcean Partners.

Orbital Sciences, a Dulles, Va.–based maker of satellites and spacecraft for communications and national security purposes, has turned to Hogan Lovells corporate partners John Beckman and Eve Howard in Washington, D.C., for outside counsel on the transaction. Howard and Orbital Sciences senior vice president of legal and business affairs Susan Herlick were honored last year with a “flex success award” by the Diversity & Flexibility Alliance.

Thomas McCabe serves as general counsel for Orbital Sciences, which is a longtime Hogan Lovells client. The company created by the merger with Alliant’s aerospace unit will be known as Orbital ATK. The transaction could signal a potential future round of consolidation in the U.S. defense sector, according to Forbes.