Three leading Am Law 100 firms celebrated the Memorial Day weekend with by grabbing key roles on a pair of billion-dollar transactions.

Cleary Gottlieb Steen & Hamilton's Victor Lewkow and Aaron Meyers—the latter of whom made partner on Jan. 1—are heading up a team working with leading Swiss firm Homburger in advising Muttenz, Switzerland-based Clariant AG on its proposed $14 billion merger with Huntsman Corp. The stock-for-stock deal, announced on May 22 and expected to close by year's end, will create a chemical industry giant, as noted by sibling publication Texas Lawyer.

Kirkland & Ellis corporate partners David Fox, William Sorabella and Shawn O'Hargan are leading a team from the firm counseling Huntsman on the deal. The Woodlands, Texas-based company, whose general counsel is former Kirkland partner David Stryker, is also being advised by Vinson & Elkins and top Swiss firm Bär & Karrer. Paul, Weiss, Rifkind, Wharton & Garrison is representing Moelis & Co. as financial adviser to Huntsman on the deal.