Patent ID: 8867087

Claim:
A printing apparatus for printing a watermark on a receipt superimposed with print data sent from a host apparatus, comprising: a storage unit for storing identification data inclusive of print commands for identifying the presence of specific print data inclusive of at least one of graphics, two dimensional (2D) code, or linear bar code in the print data received from the host apparatus, and for storing watermark data for printing a watermark; a receiving unit for receiving the print data from the host apparatus; a storage buffer for storing the print data to be printed and the watermark data for printing a watermark; and a printing control unit including a control program block responsive to said print commands in said identification data for determining on a line by line basis whether the received print data includes specific print data and would overlap the watermark data on the receipt, wherein, for each line of the received print data that is determined to include specific print data that would overlap the watermark data, the control program block further controls the printing of the watermark data to avoid printing the watermark data on that line of the receipt so as not to overlap the specific print data to be printed on that line.