This piece has 4 names of a dubai based family in black arabic calligraphy.
 
Arabic calligraphy was originally a tool for communication, but with time, it began to be used in architecture, decoration and coin design.
The thuluth script used in the above commissioned painting is one of the many forms of arabic calligraphy.It is an elegant, cursive script, used in medieval times on mosque decorations. Various calligraphic styles evolved from Thuluth through slight changes of form.