Marketo & Google Ads integration
Marketo (a leading provider of lead management solutions) has a closed-loop solution for importing offline conversions into Google Ads. Here is a very nice solution brochure. This will you to automatically export offline conversions tracked in Marketo (e.g., lead qualified, opportunity won, etc.) directly back to Google Ads, thereby allowing them to quantify the impact of their Google Ads spend against actual revenue or revenue-generating events.
You can find the Marketo technical specifications here.