The Messenger of Allah ﷺ stood up on the day of Badr and said, "Uthman has gone off on the business of Allah and the business of His Messenger, and I will pledge allegiance on his behalf." So the Messenger of Allah ﷺ allotted him a share, and he did not allot a share to anyone else who was absent besides him.
حدثنا محبوب بن موسى أبو صالح أخبرنا أبو إسحق الفزاري عن كليب بن وائل عن هانئ بن قيس عن حبيب بن أبي مليكة
إن رسول الله ﷺ قام يعني يوم بدر فقال إن عثمان انطلق في حاجة الله وحاجة رسول الله وإني أبايع له فضرب له رسول الله ﷺ بسهم ولم يضرب لأحد غاب غيره
No references are available.
[Hasan], Mizzi related it in Tahzib Kamal, 4/135, from the hadith of Fazari, at length. Hakim, 3/98, and Dhahabi agreed with him, and its chain is in Kitab Siyar by Fazari, 265. It has another route which was graded sahih. Hasan.