kˈʌpɚbˌɜːɡ wˈɜːkt ˌɔn skɹˈɪpt dɪvˈɛləpmənt ænd kˈæɹɪktɚ dɪzˈaɪn fɔːɹ sˈʌlɪvən blˈʌθ stˈuːdɪˌoʊz nˈaɪntiːnhˈʌndɹɪd nˈaɪnti fˈoːɹ ˈænɪmˌeɪɾᵻd fˈiːtʃɚ θˌʌmbɪlˈiːnə.
Kupperberg worked on script development and character design for Sullivan Bluth Studios' 1994 animated feature Thumbelina.