The owners of Leica Camera AG -- Austrian billionaire Andreas Kaufmann and private equity giant Blackstone -- are considering a sale of a controlling stake in the German camera maker in a deal that could value the company at about $1.2 billion, Bloomberg reported, citing people familiar with the matter.

HSG, formerly known as Sequoia Capital China, and Altor Equity Partners are among a handful of bidders. The Kaufmann family could re-invest following a transaction. Leica traces its roots roughly 150 years to Ernst Leitz's microscope company and was publicly traded on the Frankfurt stock exchange until the Kaufmann family took it private in 2012.