Pfizer v. Hanmi re: Infringement Litigation on Viagra Trademark for Diamond Shape and Blue Color in Korea

Pfizer’s blockbuster drug, Viagra tablet has known worldwide for its blue color and diamond shape. Right after expiry of a compound patent in Korea, many Korean companies launched generic versions of Viagra in local market. Among them, in particular, Hanmi Pharmaceutical decided to adopt their product’s shape and color as similar as possible to the original drug Viagra. As a result, Hanmi’s generic pill has almost a carbon-copy design with blue color and diamond shape with round edges. Through such a good price and clever marketing strategy, Hanmi could take nearly half the market in about 5 months after Pfizer's patent lapsed.

As an anticipated course, Pfizer filed a trademark infringement lawsuit against Hanmi but lost the first instance case. Pfizer appealed to the Seoul High Court and won the second instance case. Hanmi appealed the case to the Supreme Court late last year.

Pfizer obtained a trademark registration for Viagra’s diamond shape with blue color on February 17, 2005. (Korean TM Reg. No. 608,773) Hanmi contended that any diamond shape and blue color for drug tablets is common or conventional and thus does not have distinctiveness. Also Hanmi’s products have their own Trademark on the surface of tablet and on their package. The package is totally different from Viagra’s.

Hanmi argued that there is no likelihood of confusion between Viagra and Hanmi’s generic drug because (1) two products have their own TMs respectively on product itself as well as its package; (2) the subject drug must be distributed through doctor’s careful prescription and pharmacist’s delivery; (3) Hanmi used the diamond shape and blue color as design elements for drug tablets; and (4) such a diamond shape with blue color has been applied to drug tablets conventionally.

The Seoul Central District Court agreed with Hanmi’s arguments. However, on October 17, 2013, the Seoul High Court reversed the lower court’s decision and held that Hanmi infringed Viagra’s registered TM in diamond shape and blue color. The High Court held that the diamond shape with blue color had become a famous TM and there is likelihood of confusion about source of products having the same shape and color even though they have further TM on their surfaces and packages.

Hanmi appealed the decision to the Supreme Court. The case is pending. Pfizer has not brought the second lawsuit for damage compensation yet.