The owner of YouTube, which is defending itself against a $1 billion copyright lawsuit filed by entertainment giant Viacom, has asked a federal court to keep documents filed in the case under seal for another three months.

Viacom wants to unseal all but the most sensitive of trade secrets within two weeks and Google wants to wait until June 4. Google says it would be a "logistical nightmare" to release information piecemeal before the sides finish arguing their cases.

Initially, both Google and Viacom agreed to a protective order, which barred public access to many documents in the case. Why has Viacom suddenly changed its mind? In the filings from Friday, Viacom said it believes the law strictly requires that summary motion papers be unsealed. Some legal experts agree.