Pinning a specific PPA from Launchpad

I figured it out:

Package: *
Pin: release o=LP-PPA-ondrej-php
Pin-Priority: 1001

Pin: release o=<ppaname> where the ppa name is found by running apt-cache policy and inspecting the output:

1001 http://ppa.launchpad.net/ondrej/php/ubuntu bionic/main amd64 Packages
     release v=18.04,o=LP-PPA-ondrej-php,a=bionic,n=bionic,l=***** The main PPA for supported PHP versions with many PECL extensions *****,c=main,b=amd64
     origin ppa.launchpad.net

Use snippet below:

cat <<EOF | sudo tee /etc/apt/preferences.d/pin-ppa
Package: *
Pin: release o=LP-PPA-ondrej-php
Pin-Priority: 1337
EOF