The debut of iPhone 5 and the fast fade of Blackberry devices may well throw some curve balls at corporate mobile managers in coming quarters.

FORBES: Major Shifts Ahead in Mobile Data Consumption?

But Singh says that observing Welch s toughness with GE s managers in close quarters provided a model for running DLF: Think big and be a sector leader.

FORBES: Pay Dirt

Notable managers that lost on Apple tended to buy in more recent quarters.

FORBES: Apple -- The Guru Winners, Losers and Buyers on Stock Pullback