Reporting Resource Links:

SEARCH ENGINES

Google Safe Browsing (Phishing / Social Engineering): 
https://www.google.com/safebrowsing/report_phish/

Google Safe Browsing (Badware):

https://safebrowsing.google.com/safebrowsing/report_badware/

Bing / Yahoo Reporting:

https://www.microsoft.com/en-us/concern/bing

SECURITY DEVELOPERS
Forcepoint Threatseeker:

https://csi.forcepoint.com/

BrightCloud IP Reputation Request Change:

https://brightcloud.com/tools/change-request.php

Norton Reporting:

https://submit.norton.com/

Kapersky Reporting:

https://opentip.kaspersky.com/

Microsoft Defender Reporting:

https://www.microsoft.com/en-us/wdsi/support/report-unsafe-site-guest

Side Note about Microsoft - the reporting process is unnecessarily complicated and explains why Microsoft Defender is never ahead of security risks. If reporting to Microsoft, be prepared to send a text only document within their parameters within 48 hours or the domain is never inspected and the report is closed.