A month after Yelp, the popular online recommendation site, reportedly walked away from an acquisition bid by Google, private equity firm Elevation Partners said Wednesday it plans to invest up to $100 million in the company.

The investment firm co-founded by singer-musician-philanthropist Bono said it has agreed to make a $25 million investment in the San Francisco, California, startup through the purchase of Series E preferred stock

And Elevation plans to increase the total investment to as much as $100 million by buying shares from Yelp employees and other shareholders.

The investment would give the firm a minority stake in Yelp, said Marc Bodnick, a managing director and co-founder, in a statement.

“We have been able to grow and scale our business quickly, even in the tough economic environment of the last year — a clear indicator that we’ve only begun to realize the potential of local search,” said Jeremy Stoppelman, Yelp chief executive officer and co-founder.

Yelp, founded in 2004, said traffic to its site increased to 26 million visitors in December. The site has more than 9 million user-generated reviews of restaurants, shops, and services.

According to published reports, Google had been negotiating to buy Yelp in a deal worth at least $500 million. But the deal wasn't finalized.

The privately held Yelp had previously raised $31 million in funding and was valued around $223 million, according to a report posted on SharesPost.com.

Yelp plans to use the additional funding to deepen its market leadership position throughout the US, accelerate growth in Canada and throughout Western Europe,

Elevation Partners is a $1.9 billion private equity firm with investments in companies such as Palm. Co-founder Fred Anderson is a former CFO of Apple.