You might not be aware of this but Anti-Malware and antivirus software gets tested every year along with other similar security software. The purpose of these tests is to identify which product is the best at detecting malware. This process involves a third party organization using up-to-date versions of the software and running them all against the same malware. Many times this involves testing against older malware. However, MRG Effitas, uses Zero-Day malware to perform their tests and included Malwarebytes Anti-Malware on the list of tested applications!