7.-- Target (TGT - Get Report) said the Department of Justice has begun investigating the credit and debit card security breach at the retailer.

Target last week revealed that data connected to about 40 million credit and debit card accounts were stolen between Nov. 27 and Dec. 15. 

8.-- Shares of network and storage equipment maker Xyratex (XRTX) soared more than 27% on Monday after agreeing to be acquired by Seagate Technology (STX) for $13.25 a share, or about $374 million in cash. 

9.--  Walt Disney (DIS) said Monday that Twitter (TWTR) Chairman Jack Dorsey was named to its board.

Dorsey, who is also CEO of mobile payments company Square, will join the board immediately as an independent director. 

10.-- Microsoft (MSFT) co-founder Paul Allen this week sold a 292-acre island in northwestern Washington state for $8 million.

The island was listed in 2005 for $25 million and slashed to $13.5 million in 2009, according to The Seattle Times.

Allan Island is named after a Navy hero and not the billionaire.