Google-owned online ad-placing service DoubleClick on Friday announced that the way has been cleared to include space at Facebook.
Google had previously been shut out of the social network's advertising network, with no reasons given for the exclusion or the change of heart.
Word that the Internet titan's online advertising reach would extend to Facebook came as Google shares breached $1,000 for the first time.
Google stock was priced at $1,011.41 at the close of the Nasdaq on Friday and continued to climb in after-market trades.
Facebook shares also hit a new all-time high on Friday and closed at $54.22 a share.
"Partnership has been key to Google's success as a rising tide lifts all boats," DoubleClick senior product manager Payam Shodjai said in a blog post.
"So we're excited to announce a new way to help our clients succeed by working with Facebook to participate in FBX, their real-time bidding exchange."
DoubleClick Bid Manager is a way for marketers to buy online ad space at websites across the Internet.
Prior to Friday, Facebook did not permit the Google-owned service to sell ad space at the world's leading social network.
"Starting in a few months, clients will be able to buy inventory on FBX via DoubleClick Bid Manager," Shodjai said.
Shares of Internet search and advertising titan Google soared past the $1,000 mark after a quarterly earnings report showed that it was smoothly building its presence in the mobile area while advertising earnings rose all around, with particular help from Google's YouTube website.
Facebook becomes Google advertising ally