Groupon Inc's second-quarter loss more than doubled as it hired more than 1,000 new employees, even though the Internet daily deals company trimmed back its marketing costs.

Revenue rose to $878 million in the second quarter compared with $644.7 million in the first quarter, and rose more than 900 percent from $87.3 million in the second quarter of 2010, the company said in the S-1 filing, an update of its original filing for its initial public offering.

The numbers show that Groupon's growth slowed from the first quarter. Revenue was up 36 percent in the second quarter, below growth of 63 percent in the first quarter.

The second-quarter net loss attributable to Groupon was $102.7 million, in line with the first quarter and more than double the $36.8 million loss from the second quarter of 2010.

In June, Groupon filed to raise $750 million in an IPO. The move revealed a company growing quickly, but losing money. Some analysts have questioned a business model vulnerable to competition from companies like Google Inc, and which relies on a huge, costly sales staff to enlist merchants and handle customer service.

Some analysts worry that the company will keep having to spend large amounts of money to attract and retain customers.

Marketing costs fell to $170.5 million in the second quarter, according to the filing. Groupon spent $208 million on marketing during the first quarter, up from $4 million in the same period a year earlier.

That spending is bringing more users to the site. Subscribers jumped to 115.7 million from 83.1 million at the end of the first quarter, the company said in its filing, confirming a Reuters report last week.

But Groupon said about 40 percent of its subscribers in North America came through word of mouth, a new disclosure. That suggests Groupon did not have to spend as much on marketing to attract subscribers.

ACCOUNTING FOR MARKETING EXPENSES

Selling, general and administrative expenses rose to $273 million in the second quarter from $178.9 million in the first. That was driven by hiring: Groupon hired more than 1,000 employees in the period, lifting its sales force to more than 4,800 people.

Caving in to investor pressure, Groupon also dropped references to a financial metric it touted as a good indicator of its performance.

Concern about marketing costs led some to question Groupon's use of adjusted consolidated segment operating income, or ACSOI, which excludes online marketing expenses, stock-based compensation and acquisition-related items.

In the first quarter of 2011, Groupon reported a $117 million operating loss, but ACSOI was almost $82 million. That's partly because some $180 million of online marketing spending had been stripped out.

The company in its latest filing used a measure that includes marketing expenses, but not stock-based compensation or acquisition costs. On this basis, Groupon lost $62.3 million in the second quarter, an improvement from the first quarter when it lost $98.3 million.

Cumulative customers, or Groupon subscribers who have purchased deals, topped 23 million, up from 15.8 million as of March 31. The company sold 32.5 million deals as of June 30, up from 28.1 million at the end of the first quarter.

Average revenue per subscriber was $9, down from $10 in the previous quarter and $13 a year earlier. But the company sold an average of four Groupons per customer, up from 3.8 in the first quarter and three a year earlier.

The company generated an average of $27 in revenue from each Groupon it sold. That compares to $23 in the first quarter and $21 a year earlier.

Despite reports that some merchants are unhappy with their Groupon experiences, many still seem to be lining up to offer deals, according to the updated IPO filing.

Groupon featured 78,466 merchants as of June 30, up from 56,781 three months earlier. The merchant backlog, or the number of merchants waiting to run a deal with Groupon, topped 49,000 at the end of the second quarter, up almost 20 percent from March 31.

(Editing by Edwin Chan, Brad Dorfman and Derek Caney)

Marketing