Developer Robert Maguire is planning to build a high-rise office building in downtown Los Angeles costing an estimated $300 million marking the first major addition to the city’s skyline in 14 years.

The proposed 50-story tower will be located at Figueroa and Seventh streets and will be called 7+Fig. Los Angeles-based Maguire Properties Inc. owns the empty lot where the building of nearly 1 million square feet is to be constructed.

The company hopes to have the building at 40 percent occupancy before construction is started. The building, a wedge shaped structure, is being designed by Los Angeles architect Richard Keating. It is one of the largest of several residential, entertainment and commercial projects either planned or under construction in the downtown.

Shares in Maguire were down $1.01 in early trading Tuesday to $40.74.