From Wikipedia: The original Petz games were developed by P.F. Magic. After earning revenues of $8 million in 1997, P.F. Magic was acquired by The Learning Company for $15.8 million in 1998. In 2001, Ubi Soft (since 2003 Ubisoft) acquired the entertainment division of The Learning Company, granting Ubisoft exclusive publishing rights to 88 titles, including Dogz and Catz. After Ubisoft acquired the series, some games that were actually Japanese in origin were localized under the Petz name. For example, Petz: Hamsterz Life 2 on Game Boy Advance is a localization of Hamster Club 3, and distinctly different from its DS counterpart, although both DS Hamsterz games were also Japanese-developed but published in English territories by Ubisoft.