Is Spamhaus publishing their block list in valid JSON?

[grimelog]

I've tried setting up a URL Table in JSON format for Spamhaus's blocklist using Path expressions. However, I cannot find any expression that can successfully parse it. The JSON validators I've checked claim it is invalid JSON. However, jq can still successfully parse the list. Is this a situation that's kind of like YAML, where it's possible to write valid YAML no parser can interpret? Is this a valid JSON file?