Within the meaning of this chapter, any structure erected, maintained or used for the purpose of posting or painting advertisements or signs thereon or whereon any poster painting, advertising device or other advertising of any kind whatsoever may be placed, posted, painted or fastened shall be held to be an outdoor advertising structure or billboard; provided, however, this definition shall not be held to include any board, sign or surface used to display official notices issued by courts or public officers in the performance of official duty, or used to advertise any business or institution conducted on the premises where such structure is located, nor shall it be held to include a real estate sign advertising for sale or rent the property upon which it stands. (Ord. 1454 1, 1930)