Online advertising firm DoubleClick, which has seen its share of troubles in recent years, is now rumored to be exploring a sale to Microsoft, the Wall Street Journal reported Wednesday.

Such a deal is worth about $2 billion, according to those close to the company. Current owner Hellman & Friedman bought the company for $1.1 billion in 2005, and has sold off a number of divisions amid a massive restructuring.

DoubleClick has experienced a decent amount of turmoil since its inception in 1996. The company was the go-to company for Web developers looking to place ads on their pages during much of that decade, but the dot-com bust hit the company hard.

As ad revenues fell sharply, the company ran into financial trouble. The sale to Hellman & Friedman came as the ad market bottomed out. However, since then things have changed, with players like Google successfully restarting the industry.

Microsoft would benefit from a DoubleClick acquisition by bolstering its growing portfolio of online advertising offerings. The paper also indicated there may be interest from private equity firms as well as other large Internet companies.

Both Microsoft and DoubleClick have declined to comment on the story.