Is it permissible for me to exchange the free baby formula samples I receive from company conferences for goods I need from supermarkets, without informing them of the formula's source, and is this permissible (halal) or forbidden (haram)? If it is forbidden, how can it be made permissible?

It is permissible for a physician to accept free samples of infant formula and dispose of them through sale or gift, if it is an unconditional gift from a pharmaceutical company after a legitimate scientific conference, and it does not lead to favoritism towards the company's products at the expense of his trustworthiness with patients. He is not obligated to inform those he deals with about his ownership of them. However, if the samples are solely for the purpose of verifying product quality, then physicians are entrusted agents, and they must adhere to the condition of the granting entity. It is not permissible to accept samples if they are a bribe for the physician to prescribe this type while another is better, and this is usually the case. Therefore, what is deemed preferable is to block the means [to corruption].