Smith, Gambrell & Russell has sued the landlord of its home office, the Promenade, and management company Cousins Properties to stop an accounting firm from placing 18-foot-square signs bearing its logo high atop three sides of the building.

According to the complaint filed Aug. 22 in Fulton County Superior Court, Smith Gambrell has been the Promenade’s largest tenant since moving in shortly after it opened in 1990. The firm claims it is contractually guaranteed the right to approve any “substantial addition … or alteration” to the building’s exterior, as long as such approval is not “unreasonably withheld.”