A partnership led by El Segundo-based North Sea Capital Advisors Inc. acquired a roughly 306,000-square-foot office building near LAX from Roxborough Group and downtown-based Ruth Group for $45 million.

Newmark Knight Frank, which represented the seller, announced the deal Oct. 9. The buyer was self-represented.

NKF’s Kevin Shannon, Michael Moore, Ken White and Sean Fulp represented the seller in the transaction while NKF’s David Milestone and Brett Green secured a $39.71 million loan for the buyer.

The building, at 5901 W. Century Blvd., is 92% leased.

The seller purchased the property in 2017 and put more than $8 million into upgrading the building with a renovated lobby and common areas, a clubhouse and a dog park.

“The seller completed more than 220,000 square feet of new leases, expansions and renewals during that short timeframe at rents up to and exceeding $3.00 FSG, which are historic highs and demonstrates amazing leasing velocity for this submarket,” Shannon said in a statement.

“The recent significant value creation, as well as the future lease-up of the remaining vacancy, resulted in this offering being very well received by the marketplace,” Shannon added.

Matt McCormick, managing director of San Francisco-based Roxborough Group, said the property was still considered an “affordable option for tenants priced out of Playa Vista, El Segundo, and other Westside ‘Silicon Beach’ submarkets.”

Commercial real estate reporter Hannah Madans can be reached at [email protected]. Follow her on Twitter @HannahMadans