The Expedia Tower office building in downtown Bellevue has been sold for $168 million to a Newton, Mass. company.

HRPT Properties Trust, a real-estate investment trust, purchased the 20-story building last week. At $168 million, it is the highest priced real estate transaction in King County so far this year.

The building fetched a premium prices because it is almost entirely leased. It is located at the corner of 108th Avenue Northeast and Northeast Fourth Street.

County records indicate that the building was purchased from Hines, a Houston-based company.

The 413,000-square-foot building also is known as Tower 333.