What is the ruling on using or disposing of stationery and marketing materials obtained from a friend who is responsible for them at a company, knowing that he has the right to give them away, but not in large quantities?

An employee is not permitted to dispose of what he has been entrusted with except within the limits of what he has been authorized to do, for Allah the Almighty says: "O you who have believed, do not betray Allah and the Messenger or betray your trusts while you know [the consequence]." If the employee acts beyond the authorization, he is accountable for what he has transgressed. It is not permissible for anyone who knows this to accept it from him, and he is considered a partner in sin and accountable for what he has taken.

What was unlawfully taken must be returned to its original owner. If that is not possible, it should be returned to the company. If the beneficiary is unable to return it to the company, he should donate it as charity or pay its value towards the benefit of Muslims and charitable causes.