UPDATE 2-Qualcomm ruling affirmed, vacated in part-U.S. court

(Adds details on technology, Broadcom, analyst comments)

WASHINGTON, Dec 1 (Reuters) - A U.S. federal court on Monday affirmed a ruling against Qualcomm Inc (QCOM.O) in its long-running battle with Broadcom Corp (BRCM.O) over some video technology patents, but voided a part of the lower-court decision that said Qualcomm could not enforce the patents.

The ruling was "slightly favorable to Qualcomm" because of the part on enforceability, Charter Equity Research analyst Ed Snyder said.

The case stems from a 2005 lawsuit in which Qualcomm sued Broadcom for infringement of its patents.

The patents at issue cover advanced video compression technology, which enables the delivery of video over mobile phones. Demand for such technology is growing with the popularity of video-enabled smartphones and consumer demand for higher-quality video.

In the latest development, the U.S. Court of Appeals for the Federal Circuit agreed with a lower court that Qualcomm failed to disclose certain patents to a standards-setting body.

But the lower court, the U.S. District Court of the Southern District of California, had also ruled the patents were "unenforceable against the world."

The appeals court vacated that part of the judgment and said the remedy of "unenforceability to the world" was too broad. The ruling was sent back for the lower court to narrow its scope to certain products.

At issue in the dispute is whether Qualcomm waived its right to assert its patents by failing to disclose them to the standards-setting organization.  Continued...