The REIT plans to sell off $750 million in office assets to improve its leverage ratio. : Office Properties Income Trust might be the new kid on the REIT block, but it’s actually been around for a while in commercial real estate. On Dec. 31, Government Properties Income Trust and Select Income REIT completed their merger to form Office Properties Income Trust, based in Newton, Mass. David Blackman, president and CEO of the newly-organized REIT, says the merger enabled the disentanglement of a complicated ownership structure under the umbrella of The RMR Group Inc., an asset manager.