Hengeler Mueller and Cleary Gottlieb Steen & Hamilton have bagged lead roles on the €1bn (£677m) initial public offering (IPO) of drug packaging maker Gerresheimer – the biggest completed float in Germany this year.

Hengeler acted for Gerresheimer, with Frankfurt capital markets partner Daniela Favoccia leading a team including fellow partners Reinhold Ernst (capital markets), Matthias Blaum (corporate) and Heinrich Knepper (finance).

Cleary represented the underwriters, with Frankfurt partners Christof von Dryander and Thomas Kopp spearheading a team that advised on German and US law.

New York rival Simpson Thacher & Bartlett advised Gerresheimer on US law, including a 144A offering, with London chief Nick Shaw heading the team.

The deal, which sees Gerresheimer list on the Frankfurt Stock Exchange, is the latest in a slew of German private equity sell-offs and provides an exit for previous owner Blackstone.

Hengeler – which advised Blackstone on its acquisition of Gerresheimer in 2004 – is currently advising Siemens on the proposed IPO of its car parts division, Siemens VDO, valued at around €7bn (£4.7bn). If the flotation goes ahead, it would be the largest German placement since Deutsche Telekom in 1996.