The office market in Orange County is definitely on the rebound.

The Landmark Building, an 89,041-square-foot, four story asset located near the John Wayne Airport, just changed hands for a little less than $25 million. Avison Young brokered the deal for the sellers, 2100 Main L.P. and Bethel Holdings. Alan Pekarcik and Dan Vittone, both Avison Young principals, worked on the deal for the seller. The buyer was Property Investment Co., which had brokerage firm North American Commercial and Industrial Properties as its representative.

Landmark, at 2100 Main St., was built in 1985 and is part of the Irvine Concourse office complex. At the time of the transaction it was 60 percent leased, but the buyer plans to occupy much of the building.