Things are getting mighty testy in Silicon Valley these days: Microsoft, Yahoo, and Amazon.com have all signed up with a prominent lawyer to challenge rival Google's settlement with authors and publishers. Like Microsoft in the 1990s, Google's prominence has made it the envy and target of other companies in the industry. A Google spokesman told the Wall Street Journal that Google Books makes the market more competitive. Library and trade groups say that Google's program, which scans books off library shelves and permits users to search for phrases in those works, is an abuse of copyright laws and violates the property of authors and publishers. The lawyer for the new coalition, Peter Brantley, said his group would "develop public statements and documents" to show how Google's digital book settlement violated anti-trust laws.