If at first you don't succeed, try, and try again. It's a maxim that the management at Heller Ehrman has taken to heart over the past year as it has explored merging with one firm after another.

A little more than two weeks ago, discussions with Baker & McKenzie, the most substantive of Heller's recent merger talks, broke down due to conflicts.

And now comes word, according to sources close to both firms, that Heller is aggressively pursuing other merger options, of which the most promising is a combination with Chicago-based Mayer Brown.

A spokesman for Mayer Brown declined to comment. Calls to Heller's management were not immediately returned. A spokesman for Heller declined to comment.

The current talks between Mayer Brown and Heller, which began days after Heller's talks with Baker & McKenzie ended, represent a second effort to combine the firms.

Merger talks between the firms earlier this year were shelved because Mayer Brown management was wary of conflicts that could arise as a result of Heller's insurance recovery practice, which represents policyholders in coverage disputes with insurance companies.

Mayer Brown represents insurance companies in a variety of litigation and corporate matters.

According to one source, any merger between Mayer Brown and Heller would exclude Heller's insurance recovery practice.

It is still unclear exactly how far talks between the firms have progressed and to what extent partners at the firms know of the talks. Heller's management has been known to keep the partnership out of the loop regarding the firm's merger talks. Mayer Brown partners contacted for comment also professed to be unaware of the talks.

Heller's management has actively sought a merger in recent months to shore up the firm, which lost as many as 25 partners and missed budget projections by 15% in 2007.

Heller also reported a 3% decline in profits per partner to $1.005m (£549,000) in 2007 and the firm's revenue per lawyer fell by 5% to $805,000 (£440,000). The defections have continued in 2008. More than 35 additional partners have left the firm this year, according to reports.

Some of the departing partners over the past two years had been at Heller for decades and took chunks of business with them to other firms, including Milbank Tweed Hadley & McCloy, Goodwin Procter and DLA Piper. Heller has 14 offices and a total of 650 lawyers, while Mayer Brown has 1,800 lawyers practising at 21 offices. Previously, Heller was rumoured to be in talks with Winston & Strawn, Proskauer Rose, and other firms.

Despite the departures, there remains a loyal contingent of partners that have stayed with Heller. According to one source, many of these partners believe the firm might be able to make it through its current difficulties without merging.

The American Lawyer is a US sister title of Legal Week.