By Laura Matthews and Chiara Elisei

(Reuters) -Law firm Pallas Partners and a Swiss counsel are working on possible legal action for some Credit Suisse bond investors whose holdings were wiped out following the bank’s takeover by UBS Group AG, Pallas Partners said.

London-based Pallas Partners told Reuters on Tuesday it was in contact with a number of institutional and hedge fund investors in Credit Suisee Additional Tier 1 (AT1) bonds, with a view of forming a group and exploring litigation options in the Swiss courts as well as London and New York.

The structure of the (takeover) deal is unprecedented, subverting and wiping out the AT1s and prioritising the equity,” said Natasha Harrison, Pallas Partners’ founder and managing partner.

She said the aim was to build a litigation strategy to help those investors looking to recover their losses.

Under the UBS-Credit Suisse deal, holders of Credit Suisse AT1 bonds will get nothing, while shareholders, who usually rank below bondholders in terms of who gets paid when a bank or company collapses, will receive $3.23 billion.

Separately, some holders of Credit Suisse’s bonds have approached law firm Korein Tillery to also assess whether they have a case against the Swiss authorities’ decision to wipe out their holdings as part of the UBS Group AG deal.

George Zelcs and Chris Burke, partners at Korein Tillery, a boutique law firm specialising in complex litigation, said fewer than a dozen non-U.S. bondholders had approached them to discuss options. The firm has not yet been hired.

Neither firm named the bondholders.

Their discussions come after law firm Quinn Emanuel Urquhart & Sullivan said on Monday it was in discussions with Credit Suisse AT1 bondholders representing a “significant percentage” of the total notional value of the instruments.

A call with bond holders is scheduled to take place on Wednesday, according to Quinn Emanuel.

Switzerland’s Federal Department of Finance said it would not comment on a hypothetical situation.

Korein lawyers are examining the language of the AT1 bond contracts and whether regulators have the authority to wipe out the bonds without first doing the same for equities, the lawyers said.

(Reporting by Laura Matthews and Chiara Elisei; additional reporting by Noele Illien; Editing by Chizu Nomiyama, Dhara Ranasinghe and Emelia Sithole-Matarise)