Hotchkiss founded BigCharts.com, a maker of charts and interactive financial tools, in 1994 and managed it until it was acquired by MarketWatch in June 1999; he became president of MarketWatch late last year.
He said in a statement that he is moving on to develop a start-up now that the integration of BigCharts with MarketWatch is complete.
"The time is right for me to move on," he said. "I enjoy taking an idea and running with it, building it from the ground up, and that's what I'll be doing."
San Francisco-based MarketWatch was founded in 1997 by CBS Broadcasting and Data Broadcasting. The company in February was rumored to be in merger talks with finance Web site TheStreet.com.