Multiple CIDFont subsets occur when:
When a program creates a PDF, it sometimes "subsets" or encodes fonts to save space. If the system opening the file doesn't recognize the original font, it assigns these "F" placeholders: cidfont+f1 f2 f3 f4 f5 f6
Here is a review and technical breakdown of the string "cidfont+f1 f2 f3 f4 f5 f6" . Multiple CIDFont subsets occur when: When a program
The software that created the PDF failed to properly decode or embed the font data during export. cidfont+f1 f2 f3 f4 f5 f6
Very large PDF due to 6 subsets of the same font. Fix: