Matthew Arnold Baldwin's (MAB) banking practice has been cited as a major pull as it strikes up talks with Dentons.

The Watford and London firm, which has links with key banking clients including the Royal Bank of Scotland, Woolwich, UBS and Santander, is understood to be holding discussions with expansive Dentons with a view to the global firm absorbing MAB's banking team. MAB has also worked with Barclays for 26 years and is currently one of the 19 "preferred firms" on the bank's legal panel.

A former MAB partner said: "Matthew Arnold Baldwin does a substantial amount of work for Barclays which is the main attraction for Dentons and it also does some work for RBS which Dentons traditionally did; legacy Wilde Sapte were the main lawyers for National Westminster."

Market sources believe Dentons is not interested in the whole firm, but is rather looking to absorb its banking team.

A former MAB partner said: "God knows what happens to the rest of the firm: Dentons wouldn't be taking on a Watford high street firm would it?"

A former Dentons partner added: "Obviously whenever firms merge the client gets absorbed but what does that achieve for the client? The client ends up having less choice and one has to ask what it is the client wants MAB for? It was presumably a combination of service and price and assuming service stays the same will price stay the same?"

One banker talking about what happens when firms on banking legal panels merge said: "If the dominant firm in the merger is a non-panel firm, it may be a case of not exactly all bets are off, but that is a material change that would warrant the general counsel to revisit whether the arrangements that were in place at the time of the appointment remain valid."

Expanding empire

Dentons has made no secret of its desire of further expansion. The firm itself was created in a flurry of mergers. US firm Sonnenschein Nath & Rosenthal merged with UK firm Denton Wilde Sapte in 2010. This was followed by a three way merger between SNR Denton, Salans and Canadian firm Fraser Milner Casgrain which created Dentons. This year Dentons has announced mergers with China's largest firm Dacheng and US firm Mckenna Long & Aldridge.

A former Dentons partner talked of the firm's relentless expansion, saying: "Basically its McDonald's, you have a franchise and a brand but you are not really a unified business."

However, as the latest firm to be linked to Dentons, the MAB talks have come as a surprise to many in the market. One former Dentons partner said of the potential merger: "I think it is a teeny bit mystifying. It's potentially confusing as a vision of what a law firm ought to be."

Adding of the firm's strategy: "Immediately having merged with Sonnenschein to create SNR Denton, there was a strange moment when instead of saying let's be more global, let's be more international, let's be a single outfit, they became more nationally focused and talked about pushing people out towards Milton Keynes. It would seem it wanted to be Wragges, rather than realising that it was already what Wragges had wanted to be but couldn't manage."

MAB was founded in Watford and opened an office in London in 2005. Key areas of focus for the firm include banking litigation, asset-based lending litigation and insolvency work.

In a statement Dentons said: "Given our desire to support our clients with the deepest and broadest experience possible, at any given time we are likely to be in discussion with many groups of individuals and firms across the world. We do not, however, make any comment on such discussions until they are complete to protect the privacy of those involved and to ensure our clients are the first to be informed of any enhancement to our firm."

An MAB spokesperson said: "We have had a number of discussions with various firms as part of our longer-term strategy. We never comment on any such discussions."