in [a sale of] murabaha (cost-plus profit sale), and this is an issue that will be discussed later, if God Almighty wills. If this occurs during the option period, it is attached to the contract, and he informs [the buyer] of it in the price. This is the view of al-Shafi'i and Abu Hanifa, and I know of no disagreement with them from others. If the market price [of the item] changes while it is in his possession, then if it rises, he is not required to inform [the buyer] of that, because it is an increase in it. If it falls, Ahmad explicitly stated that he is not required to inform [the buyer] of that, because he is truthful without informing him of it. It is also possible that he is required to inform him of the situation, for if the purchaser had known, he would not have been satisfied with that price, so concealing it is a deception toward him. If he informs him of a price less than its true price without clarifying the situation, it is not permissible, because that combines lying and deception.

Section: As for if the merchandise itself changes, that is of two types:

The first is that it changes by way of an increase, which is of two kinds: one is that it increases due to its growth, such as fattening, or learning a skill, or if a separate growth results from it, such as offspring, fruit, or earnings. When he wants to sell it by murabaha, he informs [the buyer] of the price without any increase, because that is the amount for which he purchased it. If he takes the separate growth, uses the slave woman, or has intercourse with the previously-deflowered woman, he informs [the buyer] of the capital cost and is not required to clarify the situation. Ibn al-Mundhir narrated from Ahmad that he is required to clarify all of that, which is the opinion of Ishaq. The scholars of opinion (ashab al-ra'y) said regarding yields (ghalla) which he takes: There is no harm in selling it by murabaha, while in the case of offspring and fruit, he may not sell it by murabaha until he clarifies [the situation], because it is a necessary consequence of the contract. Our argument is that he is truthful in what he reports without deceiving the purchaser, so it is permissible, just as if he had not increased it. Moreover, offspring and fruit are separate growths, so they do not prevent selling by murabaha without mentioning them, just like the yield. We have already explained before that these are not among the necessary consequences of the contract. The second kind is that he performs work on it, such as fulling it, darning it, beautifying it, or sewing it. When he wants to sell it by murabaha, he must report the situation as it actually is, whether he performed that work himself or hired someone else to perform it. This is the apparent view of Ahmad; for he said: He must explain what he purchased it for and what [additional costs] became incumbent upon him, and it is not permissible