A federal judge was sharply critical on Tuesday of Napster's attempts to block trades of copyrighted music, calling the company's existing filters "disgraceful". Presented with evidence from record companies and publishers that thousands of works ostensibly included in the file-swapping service's filters were still available, US district judge Marilyn Hall Patel said at a hearing in San Francisco that something needed to change. "I think this is disgraceful," she said, noting that if a song could be found by people on the service, Napster ought to be able to block it. "You find a way to filter out [those songs] for which you can search," she told the file-swapping service, adding that if it can't block copyrighted songs, "maybe the system needs to be closed down." However, Patel stopped short of immediately ordering Napster to change its filtering technology, saying she first wanted to hear the opinion of a recently appointed technical expert. During Tuesday's hearing, the judge also did not certify class-action lawsuit proposals from music publishers or independent artists. Patel indicated that the publishers' suits may gain class-action status later, but independent artists likely would not be included. She also declined to approve motions for lawsuits against several individuals associated with Napster and venture capital firm Hummer Winblad, citing lack of evidence. Although Patel's comments put Napster on notice that she is unhappy with its filtering efforts, it's unclear whether the music-swapping service will make any changes. Napster attorneys said they are leaving decisions up to AJ "Nick" Nichols, a newly appointed court mediator who also served as a neutral court expert in Sun Microsystems' suit against Microsoft. "I don't believe she was criticising [Napster]. I believe she was asking" why songs were still available, said Jonathan Schiller, one of Napster's attorneys. "We are confident that at the end of this effort she will say we are in compliance." Patel had ordered Napster to begin blocking songs early last month, after the 9th US Circuit Court of Appeals in San Francisco asked her to loosen the noose around the company's neck. The revised injunction gave it room to continue the swapping service as long as it took all "reasonable" steps toward blocking copyrighted songs identified by the record companies. Citing the appeals court's insistence that the industry point to specific files on the service, Napster has to this point been blocking songs only when given an artist name, song title and file name. The company has blocked 311,000 individual works, although the Recording Industry Association of America says labels have identified more than 600,000 songs. During the hearing, however, Patel said Napster had a responsibility to "police" its network for copyrighted works, even if record labels had only identified song titles and artist names without listing individual file names. RIAA representatives said Tuesday that Napster is now on notice to run hundreds of thousands of additional song titles through filters. "When a judge says your efforts are disgraceful, you know something is wrong," said Cary Sherman of the RIAA's general counsel. Napster executives have insisted they are doing their best to work within the constraints of the court order. The company has its own staff looking for variations of spellings ("Metalica" instead of "Metallica," for example), has bought access to a vast database of common song misspellings, and has its own automated filter looking for likely misspellings or other filter-avoiding tricks. As proof of its success, the company points to a sharp drop in some measures of use of its service. The record industry, however, has consistently noted that despite these efforts, many or most of the songs purportedly blocked are still available. Record companies are asking the court to force Napster to improve its technology or move to a system where only songs that have been pre-approved by copyright holders can be traded. In a separate set of lawsuits, Patel also declined Tuesday to approve claims that could lead to legal action against individuals including Napster chief executive Hank Barry; John Fanning, uncle of Napster creator Shawn Fanning and co-founder of the company; and venture capital firm Hummer Winblad, which has invested $15m in the file-swapping service. Those motions had been brought by an independent producer, Matthew Katz, but Patel said he had not yet provided enough evidence to mount a case against them. However, Patel left open the possibility of future lawsuits against those or other individuals associated with Napster. She said she would rule on this issue at a later date. Serving perhaps as a prelude of future legal action, an RIAA attorney attempted to assist Katz in his arguments for expanding individuals' personal liability. The record labels "have an interest in this", said Russell Frackman, lead counsel for the RIAA. "One or more of them may be bringing a claim similar to Katz's." Although Patel said such lawsuits could eventually be heard, she refused Tuesday to let the labels discuss the issue of personal liability. "When you have the guts to put that your claim... we'll deal with it at that time," she told Frackman. Take me to the MP3 Special Have your say instantly, and see what others have said. Click on the TalkBack button and go to the Napster Debate. Let the editors know what you think in the Mailroom. And read what others have said.