Boeing is expanding its real-estate holdings in North Charleston, S.C., through a deal to buy three office buildings, with a total 178,000 square feet, on about 20 acres next to its existing 787 campus, the Post & Courier of Charleston, S.C., reported.

Terms of the deal with the South Carolina Research Authority, which was in the works for years, were not disclosed. Boeing is currently one of the tenants in the buildings.