IDG News Service — Losses grew at Motorola in the fourth quarter as regulatory investigations into its proposed acquisition by Google drag on, legal battles pile up and competition grows.

Motorola Mobility offered a few more details of its fourth-quarter results, following its release of preliminary results earlier in the month.

As expected, it reported US$3.4 billion in sales for the quarter ended Dec. 11, less than analysts were anticipating prior to the warning in early January. It posted a net loss of $80 million, compared to net earnings of $80 million in the fourth quarter last year, using generally accepted accounting principles.

While Motorola doubled the number of tablets it shipped in the fourth quarter compared to the third quarter, the number still pales in comparison to sales of the leading tablet, the iPad. Motorola shipped 200,000 tablets in the quarter. For the full year, it shipped 1 million.

It shipped 10.5 million devices in total, including the tablets and 5.3 million smartphones, during the quarter.

For the full year 2011, net revenues were $13.1 billion, up 14 percent over 2010. Net loss for the full year was $0.84 per share, compared to a loss of $0.29 per share in 2010.

Motorola said it is still hopeful that its acquisition by Google will close early this year, but it acknowledged a few hurdles. The deal has been cleared in Turkey and Russia, but while the statutory waiting period for the transaction has passed in Canada and the U.S., agencies in those countries haven't finished their investigations, Motorola said.

In December, Chinese authorities entered the second phase of their investigation, said Motorola. Next month the European Commission will say whether it will close its investigation or move on to a second-phase investigation.

Earlier this week Consumer Watchdog, a consumer advocacy group, asked the E.U. to block the merger.

When it warned that sales would be lower than expected, Motorola said that the cost of patent lawsuits and increasing competition were weighing on the company. Motorola is battling Apple and Microsoft in court over patent infringement. Earlier this week, Motorola filed a new lawsuit against Apple in Florida.

Nancy Gohring covers mobile phones and cloud computing for The IDG News Service. Follow Nancy on Twitter at @idgnancy. Nancy's e-mail address is Nancy_Gohring@idg.com