Twitter sued the US government, claiming its free speech rights are being violated by restrictions on its ability to disclose numbers of secret orders.
Facebook tightened the reins on its research methods in the wake of an outcry by members who felt manipulated by a secret study into how posts affect moods.
Google fired back at media mogul Rupert Murdoch, disputing a News Corp. complaint in Europe that the Internet titan has veered from the path of doing no evil.