(Reuters) - Dan Loeb's activist hedge fund Third Point LLC is taking a position in Pinnacle Foods Inc and is seeking a meeting with the U.S. packaged food company, people familiar with the matter said on Friday.Pinnacle Foods, the maker of packaged foods such as Vlasic pickles, explored a sale last May to Reddi-wip whipped cream owner Conagra Brands Inc , but their talks never advanced, Reuters reported at the time.Since then Pinnacle's shares have changed little, while the S&P 500 Index has risen close to 20 percent.It is not clear how big Third Point's stake in the company is or what its intentions are, said the sources, who requested anonymity to discuss the confidential matter. It is possible that Third Point does not go public with any demands, one of the sources added.Pinnacle and Third Point did not immediately respond to requests for comment.Pinnacle shares ended trading up 4 percent on the news at $61.65, giving the company a market capitalization of around $7 billion.Parsippany, New Jersey-based Pinnacle, whose brands include Duncan Hines baking products and Birds Eye frozen vegetables, has made a push toward healthier offerings, which are faster-growing and generate higher profit margins.Pinnacle bought Boulder Brands Inc, owner of Udi's Gluten Free Bread, for $975 million in 2016. (Reporting by Greg Roumeliotis in New York; Editing by Richard Chang and Tom Brown)