Hotel operator Hilton Worldwide Inc, owned by private equity firm Blackstone Group LP, will increase the size of its initial public offering to about $2.25 billion, which will let its preferred shareholders sell about $1 billion of stock, according to a source familiar with the matter.

The company expects to file with regulators for the new terms of the IPO in the first week of December, with the offering expected later in the month, the source said.

The source did not want be identified because the filing on the new terms has not yet been made public.

The news was previously reported by Bloomberg News.

Blackstone took Hilton private in 2007 in a $26.7 billion deal, which was one of the largest leveraged buyouts that preceded the 2008 global financial crisis. In September, Hilton filed for an IPO to raise $1.25 billion.Blackstone is hoping the stock market will value Hilton at around $30 billion, sources previously told Reuters. 

Founded in 1919 by Conrad Hilton, the hotel operator's brands include such high-end names as Conrad and Waldorf Astoria. Hilton has 4,041 hotels, or 665,667 rooms under its umbrella, located in 90 countries. The company itself owns or leases 157 hotels, including the Waldorf Astoria in New York and the Hilton Hawaiian Village.Blackstone declined to comment.