Is Sharing in a Sacrifice Permissible?
Question

Is it permissible to share in a sacrifice and how many Muslims can share in a sacrifice?
Praise be to Allah.Is it permissible to share in a sacrifice? 
It is permissible to share in a sacrifice if it is a camel or a cow, but it is not permissible to share in a sheep. It is permissible for seven people to share one camel or cow. 
The Prophet’s Companions (may Allah be pleased with them) shared sacrifices: seven people would share a camel or a cow in Hajj and ‘Umrah. 
Muslim (1318) narrated that Jabir ibn ‘Abd-Allah (may Allah be pleased with him) said: “On the day of al-Hudaybiyah we offered the sacrifice with the Messenger of Allah (peace and blessings of Allah be upon him), a camel on behalf of seven and a cow on behalf of seven. 
According to another report, Jabir (may Allah be pleased with him) said: We performed Hajj with the Messenger of Allah (peace and blessings of Allah be upon him), and we sacrificed a camel on behalf of seven and a cow on behalf of seven. 
Abu Dawud (2808) narrated from Jabir ibn ‘Abd-Allah that the Prophet (peace and blessings of Allah be upon him) said: “A cow on behalf of seven and a camel on behalf of seven.” (Classed as sahih by al-Albani in Sahih Abi Dawud) 
How many people can share in a sacrifice? 
Al-Nawawi said in Sharh Muslim: 
“These ahadith indicate that it is permissible to share in the sacrifice, but they are unanimously agreed that it is not permissible to share in a sheep. These ahadith indicate that a camel is sufficient on behalf of seven people , and a cow is sufficient on behalf of seven people, and each of them takes the place of seven sheep. So if a muhrim is required to offer seven sacrifices –except in the case of the penalty for hunting – and he slaughters a camel or a cow, that is equivalent to them all.”
 The Standing Committee was asked about sharing in the sacrifice and they replied: 
“A camel or a cow is sufficient on behalf of seven people, whether they are all from one family or are from different families, and whether they are related to one another or not, because the Prophet (peace and blessings of Allah be upon him) gave permission to the Sahaabah to share a camel or a cow, one animal for every seven people, and he did not say anything more specific than that.” (Fataawa al-Lajnah al-Daa’imah, 11/401) 
Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) said in Ahkaam al-Udhiyah: 
“One sheep is sufficient for one person, and one-seventh of a camel or cow is sufficient for what one sheep is sufficient for.”
For more about sharing in a sacrifice, see these answers: 45771 , 45767 , 146159 , 96741 , and 111887 . End quote.
And Allah knows best.