The proposed merged name of BCLP for the Berwin Leighton Paisner (BLP) and Bryan Cave tie-up has raised some eyebrows from partners close to both firms.

BCLP has been discussed as a possible option for the name of the combined firm, should their merger talks come to fruition, with a number of web domains registered in advance of a deal being completed.

Registered website addresses include bclplaw.com, which was reserved on 12 October, days before the firms officially confirmed they were in merger talks, while trustbclplaw.com and bryancaveblp.com and have also been registered.

A BLP spokesperson confirmed that various website domains had been registered by the firm, but that it is "too early" to confirm the name publicly.

Former partners have highlighted the loss of the Berwin brand if BCLP is selected, a name which would "bury the identity of the two firms", according to one. "Losing Berwin will mean that one of the biggest names in the London legal market – the only name attached at one point to two City firms – disappears," he said. "That would be throwing the baby out with the bathwater."

BLP was formed in 2001 by the merger of Berwin Leighton and Paisner & Co, and another ex-partner said that in the years after the deal, the firm urged partners to use the name Berwin Leighton Paisner in full. "The firm did not want to be known then by its initials," he said. "Management wanted to maintain the legacies of the two firms, so it would be quite ironic if they go with BCLP."

One source close to the firm said: "BLP must be keen to get the merger done and are going along with it. BCLP would mean they are losing the Berwin brand, which doesn't really make sense."

Another ex-BLP partner added: "It would surprise me a little if the Berwin was dropped completely, but it represents a compromise. In mergers there is a lot of argy-bargy about which name goes first. US firms are good at long names, but in the UK you have to drop one of them, so it makes sense."

However, another ex-partner suggested that the name was an effective "appeasement of both sides", due to it retaining all of the letters of both firm's names. They said: "Based on the ambiguity around the B, it makes it a little less clear whether Bryan Cave have dropped the Bryan or BLP have dropped the Berwin, so both brands are represented."

It had been thought that the two firms were intending to complete their merger as soon as 1 January next year, with partners telling Legal Week that they were expecting to vote on the deal before Christmas. However, with just over two weeks of the year remaining, an official launch date has not yet been announced by the firms.

Deloitte is advising on the tie-up, and has been working on the details of the combined firm's tax structure for inclusion in the merger proposal documents. It is understood that the firms are aiming for close financial integration, a goal that presents significant challenges due to the different tax and accounting systems used by UK and US law firms.

The two firms officially confirmed their merger talks in October. The proposed tie-up could create a 1,500-lawyer transatlantic law firm with combined revenues of about £730m.