Shodan CLI doesnt currently have a way to submit a scan for multiple IP addresses.
This shell script loops through an input file and submits a scan for each IP on each line of the input file.
The response appends to the output file "Shodanscan.txt"
Each scan IP scanned will use up 1 credit from your Shodan account
Shodan CLI
sudo apt install python3-shodan
Initialise Shodan with API Key
shodan init <api key>
(May require setting the script to be executable)
chmod +x shodanMulti.sh
./shodanMulti.sh <inputfile>