Seattle's Quicksoft Inc., a software company that helped develop the concept of ``shareware'' for more than half a million personal-computer users, has been sold to a local ex-Microsoft employee.

Bob Wallace, 41, Quicksoft's founder, said the 8-year-old company had been sold to Leo Nikora, 47, of Issaquah, Microsoft's original product manager for Windows.

Wallace - the ninth employee of Microsoft, who developed its Pascal language compiler before leaving to found Quicksoft - would not disclose terms of the deal. But he said: ``It would be difficult to put a figure on it, because it involves future considerations. If Quicksoft does well, I'll do well.''

Wallace, who acknowledged that managerial responsibilities kept him from updating Quicksoft's product line, will stay with the company as lead programmer. Nikora, as president, will assume marketing duties.

Nikora, a 25-year industry veteran with leading companies such as Xerox, Burroughs and Data I/O, said Quicksoft will keep its shareware philosophy. The term refers to software that can be copied and tried out; if the user likes it, a registration fee is paid.

``We want to build on our shareware base and reach other markets,'' said Nikora, who has used Quicksoft's flagship product, PC-Write, since 1985.