Locke Lord and Edwards Wildman Palmer have signed a letter of intent to merge, in the latest example of US mid-market consolidation.

A combination, which is dependent on further negotiations and partner approval, would create a 1000-lawyer strong firm with revenues of more than $675m (£415m).

The combined firm – which will be known as Locke Lord Edwards – will be headed by Locke Lord's current chair Jerry Clements, who announced the proposed combination with Edwards Wildman managing partner Alan Levin in a statement yesterday (10 September).

Management at both Edwards Wildman and Locke Lord will spend the next few months working on client introductions.

"Both firms have been through a number of successful combinations, but we think this one opens the door for something truly transformational," said Clements. "Our two firms share many similarities. Exceptional and well-respected lawyers; a wide geographical footprint in the United States and abroad; and highly regarded practices."

Edwards Wildman was the product of a 2011 merger between Edwards Angell Palmer & Dodge and Wildman Harrold Allen & Dixon, while Locke Lord last merged in 2007 through the union of legacy Locke Liddell & Sapp and the Chicago-founded Lord Bissell & Brook.

Dallas-headquartered Locke Lord is the senior partner in the merger, with $415m (£255m) in revenues in 2013, and 630 lawyers in 13 offices. Edwards Wildman currently counts 450 lawyers in its 16 bases in the US and abroad.

"The newly combined firm will put us in a better position to offer solid experience across a broader range of practices and industries from offices located throughout the United States, Europe and Asia," commented Levin, who is set to serve as one of the firm's vice chairs.

One challenge for the two firms will be to integrate offerings in Chicago, Hong Kong, Los Angeles, New York and Washington DC. The two firms also have bases in London, with Locke Lord having launched in the City in 2011 with seven-partner team from Salans led by Stephen Finch.

Edwards Wildman's London outpost has seen a string of partner exits in the last few months, including venture capital co-chair Shawn Atkinson, who left for Orrick Herrington & Sutcliffe, Stuart Blythe, who joined CMS Cameron McKenna, and private equity head David Ramm, who moved to Morgan Lewis & Bockius.

Other US-headquartered firms to have pursued mergers in the last year include legacy Squire Sanders and Patton Boggs, which became Squire Patton Boggs when the firms sealed their combination on 1 June.

Other proposed tie-ups in the US in recent times have proved difficult to pull off. Merger talks between Orrick Herrington & Sutcliffe and Pillsbury Winthrop Shaw Pittman, which would have created a firm with combined revenues of $1.4bn (£866m), fell through last November, due to irresolvable client conflicts.

In the same month, talks between Dentons and McKenna McKenna Long & Aldridge were called off, after partners at the latter firm voted against the tie-up.