Granted Patent
Utility
US 6,504,090 · App. 09/992,503
Apparatus and method for practice and evaluation of musical performance of chords
Inventors:
Tom Jen Tsai, Masahiko Wakita
Patented Case
View Patent ↗
Granted: Jan 7, 2003
Filed: Nov 16, 2001
Inventors
Tom Jen Tsai
Masahiko Wakita
Assignee (at issue)
YAMAHA CORPORATION
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.