On the authority of Sahih Bukhari, Tirmidhi and Musnad Ahmad that Sayyiduna Abdullah bin Umar (Radi Allahu Anhuma) has stated that Hadrat Uthman bin Affan’s (Radi Allahu Anhu) absence from the battle of Badr was because the daughter of the Prophet of Allah (Sayyidah Ruqaiyyah - Radi Allahu Anha), who was his wife, fell ill. Allah’s Prophet (SallAllahu Alayhi wa Sallam) said to him,
إن لك أجر رجل ممن شهد بدرا، وسهمه
“You will receive the same reward and share (of Maal-e-Ganeemat) as anyone of those who participated in the battle of Badr (if you stay with her).” [Sahih Bukhari, Vol. 1, Page 523, Hadith 3698]
It is has been reported by Abu Da’ud that Hadrat Abdullah bin Umar (Radi Allahu Anhuma) has said,
فضرب له رسول الله صلى الله عليه وسلم بسهم، ولم يضرب لأحد غاب غيره
“The Prophet (SallAllahu Alayhi wa Sallam) allocated for him his share and did not do so for anyone else who was absent.” [Sunan Abi Da’ud, Vol. 2, Page 18, Hadith 2726]
This was the specialty of Sayyiduna Uthman (Radi Allahu Anhu) as whosoever does not attend the battle does not get his share of the Maal-e-Ganeemat.