Dentons' merger with Chinese legal giant Dacheng has received a mixed reaction from the UK legal market, with some predicting it will lead to a spate of copycat tie-ups while others have doubts about the likely success of the union. 

The deal, which has yet to receive regulatory approval in China, will create the largest law firm in the world with around 6,500 lawyers, of which around 4,000 will come from the Chinese firm.

It will be known as Dacheng inside China and Dentons outside, but with the Chinese symbols for Dacheng at the start of the logo. 

The union marks the first deal of this scale between a Chinese and US firm and comes less than 18 months after the merger between China's King & Wood Mallesons and legacy UK firm SJ Berwin went live. 

Mark Rigotti, co-chief executive of Herbert Smith Freehills, said it was a "brave" move for both firms.

He said: "They have obviously got a strategy around scale and reach and they are pursuing it. I think it is interesting that in a firm that big there must be a significant number of the partnership that focus on domestic work where the international dimension will not be relevant. The main question is how do you bring everyone into the global vision?"

Other partners at UK firms have raised similar questions about the scale of the Chinese firm.

The head of one top 10 UK firm said: "I have not got a clue why they have done this. Why have that many lawyers in China?  I am a bit surprised. I can't see the point and this firm would not have been on my radar."

A partner at a different Chinese firm said the merger was a "step up" for Dacheng. He said: "This is positive for Dacheng – it [gives is] an additional amount of cache in the market."

Another asked:"Where are the synergies? Dacheng is not very centralised – I don't understand how they can work together."

In contrast, Alan Hodgart, founder of legal consultants Hodgart Associates, said: "It suits Dentons because they get to tell everyone they have a full scale Chinese firm unlike most of its competitors and Dacheng gets to say it has got into the international arena unlike most of their competitors."

Tony Williams, principal of Jomati Consultants, said the merger "made sense". He added: "It's a very big transaction but I wouldn't be surprised to see more in a few years. The key thing for firms with a strong Chinese capability of this sort is to persuade the Chinese clients they are the go-to firm for foreign investment. It is too early to see if Chinese clients would rather go through a Chinese firm first or would rather go direct to other international firms that they know."