A well-known trademark, whether registered or unregistered, is afforded substantial legal protection by granting the exclusive right to prevent others from using identical or confusingly similar marks on related goods or services, thereby minimizing the risk of infringement and brand dilution. For registered marks that have been recognized as well-known, this protection extends even to dissimilar goods or services—provided that the use of the mark on those unrelated products would suggest a connection to the owner of the registered mark, and that such use is likely to cause damage to the owner. 

Well-known marks enhance commercial value, boost consumer trust and loyalty, and increase market share. They also attract licensing opportunities and safeguard the brand from dilution, tarnishment, and unfair competition, ensuring long-term legal and commercial advantages.

• Rule 4 of the IPOPHL Memorandum Circular No. 2025-009 (Rules and Regulations for the Declaration and Creation of the Register of Well-Known Marks) mandates the requirements for declaration of well-known marks registration.
• Rule 5 of the same Rules prescribes the criteria for determining a well-known mark.
• The revocation of declaration is likewise mandated under Rule 16 of the same Rules. 

You may access the Rules through this link.

A declared well-known trademark can be protected in perpetuity if regularly monitored and properly maintained.

The period of protection is ten (10) years from the date of declaration and is renewable for a period of ten (10) years at a time.