Litigation giant Quinn Emanuel Urquhart & Sullivan, which boasts the second highest profits per partner among The Am Law 100, has confirmed that it has held early talks about a potential merger with Washington DC litigation and white-collar powerhouse, Williams & Connolly.

If discussions progress to the point of a deal, the union would represent the first major merger in Quinn Emanuel's three-decade history. It would create a firm with revenue of more than $1.6bn, consisting of $1.204bn from Quinn Emanuel and $420m from Williams & Connolly.

John Quinn, managing partner at Quinn Emanuel, confirmed the talks in a statement, saying: ''It is true that we had a meeting on this subject but it was very preliminary and we don't know what, if anything, will come of this."

However, chairman of Williams & Connolly Dane Butswinkas denied any plans to merge with the larger firm.

In a statement, released after the news had broken on Tuesday, he said: "While Quinn Emanuel is an excellent law firm, we are happy just the way we are. We have no plans to merge with them or any other law firm."

If a deal did go ahead it would plug Williams & Connolly, which last year had 117 equity partners earning on average $1.595m in profits, into a much larger and broader firm.

While the Washington firm remains largely a single-office firm other than a presence in New York, Quinn has offices in eight US cities and eight cities in Europe, as well as Hong Kong, Shanghai, Tokyo, Perth and Sydney.

Any deal would have to account for a wide gap in profitability between the Quinn Emanuel and Williams & Connolly partnerships. however, as Quinn's 142 equity partners earned an average of  $5.015m according to the Am Law 100.

The larger firm also boasted the highest profit margin in The Am Law 100 last year, at 67%. With a 45% margin, Williams & Connolly would somewhat dilute Quinn Emanuel's record margins.

Williams & Connolly is one of the top white-collar practices in Washington and, like Quinn Emanuel, is also known for its IP litigation practice. Quinn Emanuel has represented Samsung Electronics Co in its patent battles with Apple, while Williams & Connolly also calls Samsung a client, in addition to Pfizer, Eli Lilly and Google.

While the firms have differences in size and profitability, they share some cultural similarities. Both were formed by hard-charging, competitive and entrepreneurial litigators. Both continue to be focused on litigation and have significant intellectual property practices.

Edward Bennett Williams, who died in 1988, formed Williams & Connolly in Washington DC some 50 years ago. John Quinn, a former Cravath, Swaine & Moore lawyer, formed his firm 31 years ago.