The Library of Congress’s Copyright Office on Wednesday granted an exemption to film professors, allowing them to break the copy-protection codes on DVDs in order to create compilations of movie clips for their classes. Although such compilations are permitted under "fair use" interpretation of the copyright law, breaking the CSS security code is not. Studios had argued that the professors could use VHS tapes of the same films, but the professors countered that such tapes are often not available and those that are lack the quality of the DVDs. The ruling — along with others dealing with copyright law handed down by the Copyright Office on Wednesday — was welcomed by the Electronic Frontier Foundation, a consumers’ group, but Fred von Lohmann, an attorney with the group, commented that he was disappointed that the office had rejected a petition that would have allowed owners of DVDs to copy their movies on the iPods and other portable players.