Sahih Al Bukhari – Book of Obligatory Charity Tax (Zakat)

Volumn 002, Book 024, Hadith Number 530. 
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Narated By Anas RA : Abu Bakr RA wrote to me what was made compulsory by Allah's Apostle PBUH  and that was (regarding the payments of Zakat): Neither the property of different people may be taken together nor the joint property may be split for fear of (paying more, or receiving less) Zakat.

Lesson: lets not be fearful of becoming poor by giving Zakat. Let us follow Allah's instruction as He is the one who gave you His blessings. If we follow His instruction He will inshaAllah give more and more barakah in our stocks.

Regards
Junaid