User-agent: Googlebot
Disallow:

User-agent: Bingbot
Disallow:

User-agent: Slurp
Disallow:

User-agent: DuckDuckBot
Disallow:

User-agent: Applebot
Disallow:

User-agent: Yandex
Disallow:

User-agent: Zoom KB Crawler
Disallow:

# Block all others
User-agent: *
Disallow: /