Nevertheless, chemical patents form the basis of the chemical and pharmaceutical industryeither claiming novel substances or their applications. It is therefore of the highest interest for such companies and national patent offices to collect all previously claimed or mentioned chemical structures in patents and publications to allow for novelty checks and freedom to operate opinions. The conversion of chemical names as found in text or chemical structures in images by specialised algorithms is used by several companies to create structure and substructure searchable content for the majority of scientific publications and patent documents. Whilst the conversion of text images using optical character recognition (OCR) into chemical rule based names, trivial names or hybrid names and finally into chemical structures from the resulting OCR text is an established procedure, but it is not the topic of this present work. In contrast, the conversion of images to chemical structures (optical chemical structure recognition, OCSR) still represents a significant challenge for established software tools like Kekulé, CLiDE, OSRA and others described by Rajan et al. .