FACTS:

Petitioner McDonald's Corporation, a Delaware-based company operating a global chain of fast-food restaurants, owns the "Big Mac" trademark for its double-decker hamburger sandwiches. The mark was registered in the United States on October 16, 1979, and later in the Philippines, with the Filipino Bureau of Patents, Trademarks, and Technology (PBPTT) granting registration on July 18, 1985. McDonald's was franchisee McGeorge Food Industries runs its Philippine operations. In opposition to McDonald's, respondent L.C. Big Mak Burger, Inc., a local corporation operating fast-food outlets and snack vans in Metro Manila and nearby provinces, sought to register the "Big Mak" mark on October 21, 1988. McDonald's contested this application, asserting "Big Mak" was a colorable imitation designed to mislead consumers due to its similarity with "Big Mac." Despite no response from respondent, McDonald's filed suit for trademark infringement and unfair competition in the Makati Regional Trial Court (RTC) June 6, 1990, securing a temporary restraining order and later, a preliminary injunction against the respondents, who admitted using the "Big Mak" name but disputed McDonald's exclusive rights, referencing prior registrations by other entities. McDonald's countered it had acquired these prior rights, stating previous registrations provided no protection or had been assigned to them.

ISSUES:

1. Procedurally, whether the questions raised in this petition are proper for a petition for review under Rule 45.

2. On the merits

   a. Whether respondents used the words "Big Mak" not only as part of the corporate name "L.C. Big Mak Burger, Inc." but also as a trademark for their hamburger products.

   b. Whether respondent corporation is liable for trademark infringement and unfair competition.

RULING:

1. On the procedural issue

   • The Court holds that despite the existence of questions of fact, due to the contradictory findings of fact between the RTC and the Court of Appeals, the petition is accepted under the exception to Section 1 of Rule 45.

2. On the merits

   a. Use of "Big Mak" as Trademark

    - The Court finds that respondents used "Big Mak" as a trademark for their hamburger products, evidenced by plastic wrappings, bags, and cash invoices simply referring to their hamburger sandwiches as "Big Mak."
   

   b. Trademark Infringement and Unfair Competition

    - **Trademark Infringement** Applying Section 22 of RA 166, the Court holds that "Big Mak" is a colorable imitation of "Big Mac," likely to cause confusion among consumers.
   
    - **Unfair Competition** The Court finds respondent corporation liable for unfair competition as their use of the "Big Mak" mark gives the general appearance that their hamburger products are associated with McDonald's "Big Mac."
   

PRINCIPLES:

1. Exclusive Ownership of Trademarks

   • Ownership and registration of a trademark, here "Big Mac," entitle the owner to protection against infringement.

2. Trademark Infringement

   • Trademark infringement exists when a subsequent mark is a colorable imitation of a registered mark, creating confusion among the public.

3. Unfair Competition

   • Defined as the employment of deception to pass off one’s goods as those of another who has already established goodwill for their similar goods.

4. Dominancy Test and Idem Sonans

   • Similarity between marks is assessed based on the dominant features and sound, leading to potential confusion.

5. Presumption of Good Faith

   • The law assumes good faith; the burden of proving bad faith or deceptive intent lies on the party alleging unfair competition.

6. Conflicting Findings Exception

   • The Supreme Court may accept petitions raising factual questions where there are conflicting findings between the lower courts.