Perkins + Will, the global design firm, has sold its Connecticut office to two of its principals.

Stevanie Demko and Kathyann Cowles bought the Glastonbury office, near Hartford, in March, say sources close to Perkins + Will. The two designers have renamed the firm Id3A and have reportedly kept many of Perkins + Will’s clients in the area. Id3A has also retained most of the office's employees, which numbered around a dozen earlier this year, according to sources.

Terms of the deal were not disclosed. A spokeswoman for Perkins + Will did not return calls for comment, nor did Demko.

The Glastonbury outpost was once the firm Ai, which Perkins + Will acquired in 2005. The office struggled, as it had to compete for work against Perkins + Will’s branches in nearby New York and Boston, say sources.

Though many large firms had to downsize in the recession, Perkins + Will fared relatively well; it did not close a single office in the last few years. Today, the firm, founded in 1935 in Chicago, has 20 North American offices and three overseas, with a total of 1,500 employees.