NEW YORK CITY-Helping to get the third quarter off to a goodstart for Manhattan office leasing, digital marketing agency LBi USis nearly doubling its headquarters space with a move to 11 W. 19thSt. While the 52,000-square-foot deal goes somewhat against thegrain for office relocations in that the tenant is increasing itsfootprint as it consolidates from three other sites, it illustratesa pair of trends.

One is the popularity of Midtown South, which Cushman &Wakefield says has more than doubled its year-to-date leasingvolume over 2009. The other is the “densification” of office space,as firms seek not only to fit as many employees as possible into agiven amount of square footage but also to increase efficiency andinteractivity.

At its midyear press briefing Wednesday, C&W, whose JamieKatcher and Frank Coco coincidentally figured in the LBi deal,released figures showing that YTD leasing in Midtown South is 236%over last year at 2.3 million square feet. That compares to a 102%increase in Midtown and a 14.3% gain in Lower Manhattan.