I have looked in a good many sources for this expression, and I am at a loss.
It is in the context of an Income and Expenditure Statement (収支報告書) I am translating, and is found adjacent to 寄付金 and ランチョン:
共催収入 寄付金
共催収入 ランチョン
The closest I can get is "joint sponsorship income."
How would you translate 共催収入?