User-agent: Googlebot
Disallow:

User-agent: AdsBot-Google
Disallow:

User-agent: Googlebot-Image
Disallow:

User-agent: Bingbot
Disallow:

User-agent: DuckDuckBot
Disallow:

User-agent: Yandexbot
Disallow:

User-agent: Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Disallow:

User-agent: Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2272.96 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Disallow:

# https://ahrefs.com/robot
User-agent: AhrefsBot
Disallow: /

# Alexa
User-agent: ia_archiver
Disallow: /

# https://www.semrush.com/
User-agent: SemrushBot
Disallow: /

# https://www.seoprofiler.com/auditbot
User-agent: sp_auditbot
Disallow: /

# https://majestic.com/
User-agent: MJ12bot
Disallow: /

# http://moz.com/
User-agent: dotbot
Disallow: /

# http://openlinkprofiler.org/
User-agent: spbot
Disallow: /