The 17 partners who departed Washington law and lobby firm Patton Boggs last week have scattered to several other national law firms.

In Washington, the five partners are David Farber, a health care regulatory lawyer who joined King & Spalding’s Food and Drug Administration practice; Ugo Colella, a business litigation specialist who joined Thompson Hine; environmental lawyers Henry Chajet and Robert Horn, and R. Brian Hendrix, a health and safety law specialist, all of whom are now at labor and employment firm Jackson Lewis.

Patton Boggs’ Dallas office, its second largest after Washington, took a much bigger hit. There, 24 attorneys — including 12 partners — left to open Holland & Knight’s new Dallas office, Holland & Knight announced last week. The group specializes in corporate and commercial finance, mergers and acquisitions, restructuring and bankruptcy. The top partners now leading the Holland & Knight group include Michelle Suarez, former managing partner of Patton Boggs’ Dallas office, and Jim Chadwick, former co-chair of Patton Boggs’ business department.

Covington disqualification upheld

A court of appeals last week upheld a ruling that disqualifies Washington law firm Covington & Burling from representing the state of Minnesota in an environmental lawsuit against 3M, a former client of the firm’s.

A lower court last year ordered Covington to stop representing the state in a 2010 lawsuit that accuses 3M of polluting waterways with fluorochemicals used in making Post-It notes and other products. The firm previously did work for 3M in the 1990s, representing the company on regulatory matters before the Food and Drug Administration, including advocating that products containing fluorochemicals were safe for consumers. Covington appealed the decision.

The court of appeals affirmed the lower court’s ruling that Covington, which was hired as outside counsel in the environmental litigation, had a conflict of interest and did not do enough to ensure that confidential information about 3M — that the firm may have gained from its previous work with the company — was kept from attorneys for the state of Minnesota, who are now suing 3M.

The firm declined to comment, but Covington Chairman Tim Hester has previously said the firm had no conflict representing the state of Minnesota, and that none of 3M’s confidential information was used by Covington lawyers against 3M.