Recently patented rights affect the competitive power of each country. Specially the situation of that country will be superiority if one country has lots of basic invention patents in advanced technology. In the near future, research results in universities or research institutes should be involved with patent application so that the investment of research funds improves our technology. Alloy is used to adjust magnetic characteristic in invention for magnetic recording medium. In this case there must be cautious in make out the patent claims of invention about such alloys. The patent for alloy invention is considered with following standard. (1) composition range and structure aspect according to the need of a composition metal (2)characteristics of the alloy and for use.