Viacom, Walt Disney, Microsoft and other media companies have agreed to a set of guidelines to protect copyrights online but Google, owner of the Web's biggest video site, was notably absent from the pact.
Interest in online video has boomed over the last two years, putting media content owners at odds with Web sites that host videos when their users upload copyrighted material without permission.
Google and its YouTube video-sharing site face a $1 billion copyright infringement suit filed by Viacom, for example.
"These principles offer a road map for unlocking the enormous potential of online video and user-generated content," Disney Chief Executive Bob Iger said in a statement.
The group also included News Corp.'s Fox and MySpace units, CBS, General Electric's NBC Universal, and online video services such as Veoh Networks and Dailymotion. They agreed to use technology to eliminate copyright-infringing content uploaded by Web users and to block any pirated material before it is publicly accessible.
CNBC is a unit of NBC Universal.
Although Google was not part of the group announced at an Internet conference in San Francisco on Thursday, analysts said it will likely have to adhere to the set of guidelines if it becomes standard industry procedure.
"Once an industry initiative is formed, Google will be forced to accept the common model rather than use its own solution as a competitive differentiator," Forrester Research analyst James McQuivey said.
Google could not be reached for comment. A source familiar with the matter said the Web search leader is in talks to possibly join.
Among the provisions in the pact is an agreement to implement "commercially reasonable" content identification technology by the end of this year, which some including the MySpace social networking site has already done.
"These principles will enable innovative technology and great content to come together to spur greater innovation and, most importantly, much richer entertainment experiences for consumers," Viacom CEO Philippe Dauman said in the statement.
In what may be a preemptive move, Google this week unveiled new technology that allows content owners to automate the identification of copyrighted material on its YouTube online video service. The technology does not yet allow the blocking of copyrighted content from being uploaded.
"The pressure on Google to go along with this cooperative initiative will be intense, as the fate of existing lawsuits will likely hinge on Google's acceptance of the common solution," McQuivey said.