Nielsen and ComScore in Legal Tussle Over Patents

Nielsen and comScore are volleying patent lawsuits, each accusing the other of treading on its intellectual property rights.

Last Thursday Nielsen filed against comScore in the latter’s home state of Virginia, claiming it trespassed on patents related to online audience measurement. Yesterday comScore countersued in the same U.S. district court, leveling similar accusations.

Nielsen’s filing claims comScore violated five of its patents. Two relate to metering of computers and Web content; two more involve the measurement of content displays; and one covers “network resource monitoring.”

Both companies are seeking unspecified damages.

Nielsen has some history of patent-related litigiousness. In 2005 NetRatings, not yet a subsidiary of Nielsen, filed suit against Visual Sciences, SageMetrics, and Sane Solutions.

“While we support vigorous competition in the marketplace, that competition must be fair and respect intellectual property rights,” Nielsen said in a statement. “Nielsen does not take such matters lightly and only after thorough analysis and consideration did we file this action. We look forward to a fair and appropriate resolution.”

Nielsen declined to comment further, and comScore did not reply to a request for comment this morning.

Nielsen has suffered some product setbacks since mid-last year, when it admitted flaws in its Web measurement systems had led it to undercount online time-spent data and perhaps other metrics. It instituted a fix in November that was to take effect with its December data, and urged clients to temporarily limit their use of several of its products.

Nielsen is also updating its methodology on ad expenditure, and has recently declined to supply such data to media outlets. It’s not clear if this is related to the undercounting fiasco.