We decided to accept his proposal.
会社に改善案の申し出でを提出した。
I submitted a proposal for improvement to the company.
Standard kanji spelling.
Variant with simplified okurigana; less common but still used.
Derived from the verb 申し出る (もうしいでる, 'to propose, to offer') via its continuative form. The spelling 申し出で reflects the older okurigana convention.