Swiss watchmaker Patek Philippe, the maker of $10,000-plus Calatrava watches, may be put up for sale, analysts at German investment bank Berenberg said citing industry talk. The 180-year-old watchmaker could fetch $8 billion to $10 billion, the analysts wrote. Patek Philippe has been owned by the Stern family since 1932, and Thierry Stern became the company's President in 2009.