However, the absence of a notice does not signify that the work is public domain, nor is such a notice required by law to retain ownership. If you are unsure as to the shareware status, check to see if there is a notice with the font that states that it is shareware, and the conditions under which it can be used. If such a notice is not available, and you don't know where the font came from, it is a big risk to assume that it is shareware. If someone passes the fonts along without the documentation, trouble begins. Even if you get a font through a newsgroup posting, it does not automatically mean it is shareware either.
People make mistakes.
The anonymity of typeface origins and their designers is an unfortunate situation that has become increasingly detrimental to the field of typeface design. Before the democratization of type, which resulted from the introduction of personal computer technology, just over a decade ago, there existed an established collection of typefaces that were familiar to graphic designers, typesetters, and others who worked with type. The introduction of new typefaces was a slow process that allowed ample time for the type community to become accustomed to the new designs. Because everyone in the industry could identify typefaces, graphic designers and typesetters had grown accustomed to leaving out credits for the typeface names or typeface designers, although they did credit their own work as well as that of photographers, printers and others whose work was included in the design piece. Today, typefaces are being introduced into the market-place faster than any one can keep up with the selection.