The document was duly signed by the inspector.

这份文件已由检查员签妥。

《牛津词典》

This Agreement commences on the date when the company receives the Subscription Form duly signed and affixed with the Subscriber's company chop.

本协议在本公司收到会员已妥善签署并盖上印章的《订阅表格》当日正式生效。

youdao

After sound and definite negotiations, the contract is read and scrutinized carefully, duly signed by the contracting parties and enacted as follows.

经过合理明确的谈判，本合同已由合同双方仔细审阅并签字。

youdao

Shareholders duly signed up to the rights issue, and by the end of that year, not only had the chief executive lost his job, but they'd lost about 90% of their shares' value.

BBC: Royal Bank's obstacle course