The collapse of automotive giant General Motors has handed roles to at least 15 law firms so far in one of the largest restructurings to date.

Clifford Chance (CC) has taken a high-profile role advising GM Europe on the restructuring of its business, which includes the proposed sale of its flagship Opel brand. CC's team was led by Frankfurt-based corporate restructuring partner Kolja von Bismarck.

GM Europe has also instructed Weil Gotshal & Manges with London head and corporate partner Mike Francies leading along with Frankfurt-based tax partner Juergen Boerst.

Baker & McKenzie has been instructed by the manufacturer on employment matters, fielding German employment law partner Guenther Heckelmann, while Herbert Smith's German ally Gleiss Lutz was brought in to advise on EU issues and state aid with a team led by Brussels-based partner Ulrich Soltesz.

Shearman & Sterling has taken the role as lead adviser to the German Government, which has been heavily involved in the discussions due to GM's applications for state aid. German co-head and global M&A co-head Harald Selzner is the lead adviser for the US firm.

The two main bidders for Opel – Italian car maker Fiat (which has now pulled out of a bid) and Canadian car parts manufacturer Magna – instructed US firm Sullivan & Cromwell and Gleiss Lutz respectively, with Frankfurt-based M&A partner Konstantin Technau leading for Sullivan and Frankfurt-based M&A partner Wolfgang Bosch representing Gleiss.

Fiat was also believed to have instructed Shearman's Mannheim-based spin-off firm Schilling Zutt & Anschuetz.

Rippelwood Holdings, which had shown early interest in the brand, turned to Freshfields Bruckhaus Deringer.

Opel, meanwhile, instructed local German firms Wellensiek and Apitzsch to advise the management and the workers' council respectively.

Simmons & Simmons advised the State of Hessia – where Opel's head office is based – on the transaction. The team was led by corporate partners Ulrich Brauer and Michael Bormann and included insolvency specialist Regina Rath.

The restructuring of the US arm of the business has also seen Weil Gotshal take a role, alongside Dewey & LeBoeuf, Jenner & Block and Honigman Miller Schwartz and Cohn. Cadwalader Wickersham & Taft is lead counsel for the US Treasury Department.

A partner at a US firm commented: "Legally this deal is not groundbreaking, I expect it would be fairly straight forward. However, it will keep a large number of people busy and as such is a very nice and juicy instruction to have, especially for Weil Gotshal as lead US counsel. I have absolutely no idea how much fees GM will pay all of these firms, but I would assume it is millions of dollars."