Microsoft Corp (MSFT.O) is demanding $6.9 million interest from Samsung Electronics in a dispute over smartphone patent royalties, according to a lawsuit unsealed by a New York federal court on Friday. Microsoft is asking the court to rule that it did not breach a business collaboration agreement with Samsung, and that Samsung must pay interest on more than $1 billion in royalty payments which it delayed in protest at Microsoft’s planned purchase of rival Nokia’s handset business. A redacted version of the lawsuit was filed by Microsoft in August.