/usr/share/man/man1/gemtopbm.1.gz is in netpbm 2:10.0-15ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man1/gemtopnm.1.gz
/usr/share/man/man1/gemtopnm.1.gz