Summary Box: Tech cos. team up to fight email scam

THE PROMISE: A new system is being developed to combat email phishing scams, which try to trick people into giving away passwords and other personal information by sending emails that look as if they come from a legitimate bank, retailer or other business.

BIG NAMES: Fifteen major tech and financial companies are behind this, including Google, Facebook and Bank of America.

MECHANICS: It builds upon existing spam-fighting systems to authenticate legitimate messages and weed out the rest.