National fast food chain says it first heard of unusual activity involving payment cards on Dec. 19.
Judge says consumer suit can proceed because victims suffered actual losses.
Three of four allegations in a class action suit filed by financial institutions against Target can proceed.
Website makes it easy for consumers to send messages to Congress urging tougher security standards for retailers.
Credit unions saw 16% of their cards hit by fraud in 2013, compared to 12% for community banks and 14% for large banks.
The restaurant chain is the latest retailer to suffer a card breach, according to security blogger Brian Krebs.
If banks can beat retailers in the race to adopt EMV technology, they may have a fraud liability advantage.
A new report from Aite Group says 70% of credit and debit cards will have EMV chips by December 2015.
The big box retailer will launch the proprietary credit cards June 23.
Gregg Steinhafel steps down from his position as CEO and board chairman following Target's major data breach.