Last winter, Heller Ehrman inaugurated its new office space on Rhode Island Avenue Northwest with a festive reception that included drinks, hors d’oeuvres, and even a choir performance. It was a celebration of the firm’s commitment to the Washington market, where it has bulked up practices like antitrust and bankruptcy.

But the San Francisco-based firm is finding that rapid expansion sometimes leads to rapid contraction. Last week four intellectual property attorneys — former practice co-chair Colin Sandercock, John Isacson, Paul Booth and David Laub — jumped ship to Proskauer Rose, a New York-based firm whose $1.1 million profits-per-partner well outstrip Heller’s $885,000.