Final answer:
The inclusion of non-business days in periods refers to periods with no equivalent day on the expiration month. This is done to ensure equal opportunity for exercising rights or fulfilling obligations.
Step-by-step explanation:
In Article 5, the inclusion of non-business days in periods refers to periods with no equivalent day on the expiration month. This means that if an expiration date falls on a non-business day, such as a weekend or a public holiday, the expiration is moved to the next business day. This is done to ensure that all parties involved have equal opportunity to exercise their rights or fulfill their obligations.