Fish & Richardson disclosed layoffs and departures of 49 lawyers and technology specialists — nonlawyers with scientific or technical expertise who work on patent matters — in the past three months.

In a Jan. 30 written statement, the firm said that the legal staff members have left since November or are in the process of leaving the firm. Fish & Richardson also disclosed that the number includes four dismissals made on Jan. 30.

The firm, which is known for intellectual property, litigation and corporate matters, said the departures and layoffs occurred at 10 of the firm’s 11 U.S. offices.

“Many of these departures occurred as the result of year-end performance evaluations, but others were based on purely economic decisions,” stated the firm.

The firm also stated that the cuts were prompted by a combination of “unprecedented levels of economic uncertainty” and a “significantly below normal” attorney attrition rate.

“We have reduced our workforce after strategically evaluating our projected needs in all of our practice groups,” stated the firm.

The announcement follows the firm’s Jan. 29 announcement that it laid off 30 members of its nonlawyer support staff in eight of its U.S. offices.