Partners at both firms confirmed the discussions in a deal that promises to greatly bolster the London arm of the 500-lawyer Duane Morris and hand it a network of Eastern European offices.
One US Altheimers partner commented: “Duane Morris has made an approach and Altheimers is currently considering that approach. The talks are high level, but at a reasonably early stage.”
It is understood that an initial approach was made by Duane Morris in the past four weeks as part of a growth strategy that has seen it almost double in size in the past five years.
The combined firm would have around 800 lawyers and a turnover in excess of $300m (£180m), catapulting Duane Morris into the US top 50 by size.
The move, however, comes as Duane Morris continues a separate bid to bolster its six-partner London practice — which it acquired three years ago through a takeover of niche City firm Geisler & Laws — with a second UK merger. Partners at the firm have indicated that a UK merger could be finalised in a matter of months.