Google downplayed a lawsuit against its video service, two days after the search giant revealed the legal action.

"This is a small lawsuit over a single video that appeared briefly," a Google spokesperson said in an emailed statement.

In a quarterly document filed with the US Securities and Exchange Commission on Wednesday, Google revealed that Google Video, a video-sharing site, has been the subject of a copyright infringement case. Google did not disclose additional details about the suit, and the US District Court for Northern California, where the company is based, doesn't list any cases relevant to the video service.

Google could not offer any additional details about the suit, according to the spokesperson.

The lawsuit has caught the attention of industry observers who have already been wondering if Google might become the target of expensive lawsuits after it digests its planned acquisition of YouTube, the online video-sharing service.

Google launched Google Video earlier this year but the popularity of its offering has paled compared to that of industry leader YouTube. In October, Google announced its plans to acquire YouTube for $1.65 billion in stock.

The same day the companies announced the acquisition, they both separately announced deals with a few content publishers to ensure their content is legally posted on the sites and to prevent the posting of illegal content.

Both sites enable users to post videos that may not be properly licensed and they both have launched initiatives to try to combat illegal content.

Google Video has a procedure by which copyright owners can alert Google that their content has been illegally posted. Google responds by quickly removing the content from the site, the spokesperson said.