Sahih Muslim | Book 10 | Chapter 4

Narrated by Ibn 'Umar (Allah be pleased with them)
Ibn 'Umar (Allah be pleased with them) reported Allah's Messenger (may peace be upon him) as having said this: One amongst you should not enter into a transaction when another is bargaining.

Narrated by Ibn 'Umar (Allah be pleased with them)
Ibn 'Umar (Allah be pleased with them) reported Allah's Messenger (may peace be upon

him) as saying: A person should not enter into a transaction when his brother is already making a transaction and he should not make a proposal of marriage when his brother has already made a proposal except when lie gives permission.

Narrated by Abu Huraira
Abu Huraira reported Allah's Messenger (may peace be upon him) as saying: A Muslim should not purchase (in opposition) to his brother. This hadith has been narrated on the authority of Abu Huraira through another chain of transmitters but with a slight change of words.

Narrated by Abu Huraira
Abu Huraira reported Allah's Messenger (may peace be upon him) as saying: Do not go out to meet riders to enter into transaction with them; none of you must buy in opposition to another, nor must you bid against one another; a townsman must not sell for a man from the desert, and do not tie up udders of camels and sheep, and he who buys them after that has been done has two courses open to him: after he has milked them he may keep them if he is pleased with them, or he may return them along with a sit of dates if he is displeased with them.

Narrated by Abu Huraira (Allah be pleased with him)
Abu Huraira (Allah be pleased with him) reported that Allah's Messenger (may peace be upon him) forbade the (people) meeting the caravan (for entering into business transaction with them), and the selling of goods by a townsman on behalf of a man of the desert, and seeking by a woman the divorce of her sister (from her husband), and outbidding (against one another), and tying up the udders (of animals), and buying of (things) in opposition to one's brother. This hadith has been narrated through another chain of transmitters.

Narrated by Ibn Umar (Allah be pleased with them)
Ibn Umar (Allah be pleased with them) reported that Allah's Messenger (may peace be upon him) forbade the outbidding (against another).