Redmond, Wa.— Microsoft Corp. agreed Sept. 15 to buy Visio Corp. (Seattle, Wa.) for about $1.3 billion in stock. Each share of Visio common stock will be exchanged for 0.45 shares of Microsoft common stock pending regulatory and Visio shareholders' approvals. The companies say acquiring Visio's enterprise-wide business diagramming and technical drawing software capabilities will help Microsoft further increase its customers' productivity. Visio will become the "Visio Division" within Microsoft's Business Productivity Group and will be overseen by Microsoft senior vp Bob Muglia. Jeremy Jaech, Visio's president and ceo, will also manage the Visio Division as a Microsoft vp, reporting to Mr. Muglia. Visio will operate within Business Productivity with no immediate changes. Its products will remain separate but complementary to Microsoft Office.