Roy E. Disney Firm Building Agoura Offices

Shamrock Holdings Inc., wholly owned by the Roy E. Disney family, has begun construction of Shamrock Plaza, a $5.1-million office building in Agoura Hills at 28720 Roadside Drive.

Designed by Los Angeles architect Barry Greene and constructed by Dynamic Builders Inc., the three-story, 70,000-square-foot structure is due to be completed in the spring.

Zugsmith & Associates is exclusive leasing agent.

Shamrock Holdings’ interests include Shamrock Broadcasting Inc., which owns and operates three television stations and nine radio stations; ranch properties and other real estate, and diverse investments. Shamrock recently acquired Central Soya, a Fort Wayne, Indiana-based international and food-processing company with annual net sales of $1.73 billion.