LivingSocial is raising $400 million in a deal that doubles the valuation of the daily deals service from its last fundraising round in April, according to a person familiar with the matter.

LivingSocial, the second-largest daily deal company in the U.S. behind Groupon Inc, disclosed the new fundraising round in a filing with the Securities and Exchange Commission on Wednesday.

According to the filing, LivingSocial has raised $176 million, with plans to raise $400 million in total. The company did not disclose the investors, or the valuation, though a person familiar with the matter said the company's valuation was roughly $6 billion.

LivingSocial was planning to go public earlier this year in an IPO that may have raised about $1 billion at a valuation of $10 billion to $15 billion. In the summer, the company picked Bank of America Merrill Lynch, JP Morgan and Deutsche Bank to lead-underwrite the IPO.

However, the stock market slumped in July and August, putting a lot of IPOs on hold. Groupon finally went public in early November, but the company's shares have slumped below its $20 IPO price in recent weeks.

The New York Times reported last month that LivingSocial was aiming to raise $200 million at a valuation of more than $5 billion.

In April, LivingSocial raised $400 million in a round of funding that included LightSpeed Venture Partners and Amazon.com, giving it a value of about $3 billion.

Online retail giant Amazon.com Inc is also an investor in LivingSocial.