You recognize a registered trademark by the symbol of a circle-R following the trademark name or graphic image. Various typographic symbols show copyrights and patents. The presence or absence of a symbol does not change the validity of the registration, but a best practice is to use a circle-R or circle-C for copyrights every time you mention your intellectual property in print. These symbols give legal grounds for claiming damages in trademark litigation. The following is a list of some typical marks you can use on a web page, in written content, or even in a marketing letter.

• TM: The TM sign shows the brand name for an unregistered trademark classified as a product (classes 1 to 34). The owner uses this sign to mark what they believe is their brand mark.
• SM: The SM sign is identical to the TM sign except it designates a service mark (classes 35 to 45).
• ®: Use the ® symbol once you register a trademark or service mark. It shows that the country authority has approved the registration.
• ©: Use the © symbol to mark a copyright. The word copyright is substitute sign for Follow it with the year of the publication and owner's name. Use it whether the work has obtained copyright registration or not.
• Patent Pending: The phrase Patent Pending shows that you filed a patent application but cannot guarantee the application's approval.