Does haraam wealth affect the acceptance of the sacrifice (udhiyah) if it was bought by a group, some of whose wealth is haraam?
Question

                If a group of people share in offering an udhiyah, such as if seven people share in a cow or camel, and the wealth of one of the people who joins us is haraam, and he paid his share of the udhiyah with haraam wealth, will that affect the udhiyah?
Praise be to Allah.It is permissible for seven people to share in the udhiyah, if it is a camel or a cow, because of the report narrated by Muslim (1318) from Jaabir ibn ‘Abdullah (may Allah be pleased with him) who said: We offered the sacrifice with the Messenger of Allah (blessings and peace of Allah be upon him) in the year of al-Hudaybiyah, a camel on behalf of seven and a cow on behalf of seven. 
Ibn Qudaamah (may Allah have mercy on him) said: It is permissible for seven people to share in a camel or a cow, whether the sacrifice is obligatory or voluntary, and whether all of them want to offer a sacrifice, or some of them want to do so and the others just want the meat.
End quote from al-Mughni (3/296) 
For more information, please see the answer to question no. 45757 
The share of each of those who join together, if they are seven, is one seventh of that udhiyah. It does not affect the partners in that case if one of the partners shared in that udhiyah with them using haraam wealth, if they were not aware of that, because each of them is responsible for his own efforts and actions, and no bearer of burdens will bear the burden of another. 
But if the partners were aware of the situation then they should not help him in disposing of his haraam wealth and benefitting from it. Rather what they should do is denounce him for that, and it is prescribed for them to shun him so as to deter him from his sin and from consuming haraam wealth. 
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