The following are lists of U.S. patents, current and expired, granted
to Emmett Chapman.
Licensing inquires are welcome.
| Patent No. | Date Issued | Date filed | Description |
| 8,324,489 | Dec.4, 2012 | May 7, 2009 | "Railboard"® integral neck, fingerboard and "Rail" frets cut from one metal piece. view patent. |
| 7,629,521 B1 | Dec. 8, 2009 | Oct. 14, 2008 | "Divided Truss Rod"™, a "4-way"™ system in a single rod. view patent. |
| 6,462,259 B1 | Oct. 8, 2002 | Oct. 30, 2000 | "Flaps"™ Nut assembly for stringed musical instrument. view patent. |
| 6,452,077 B1 | Sep. 17, 2002 | Feb. 10, 2000 | Disengagable string damper for a musical instrument (Ned Steinberger co-inventor). view patent. |
| 6,369,306 B2 | Apr. 9, 2002 | Dec. 18, 2000 | "Rails"® fret system for stringed musical instruments. view patent. |
| 6,043,422 | Mar. 28, 2000 | Feb. 1, 1999 | "The Block"® Compartmentalized pickup module for stringed musical instruments. view patent. |
| Patent No. | Date issued | Date filed | Date expired | Description |
| 5,285,710 | Feb. 15, 1994 | Jun. 29, 1992 | Feb 15, 2011 | Adjustable bridge for a stringed musical instrument. view patent. |
| 5,140,887 | Aug 25, 1992 | Sep 18, 1991 | Aug. 25, 2009 | Stringless fingerboard synthesizer controller. view patent. |
| 5,079,536 | Jan 7, 1992 | Mar 5, 1990 | Jan. 7, 2009 | Pressure transducer for musical instrument control. view patent. |
| 4,953,435 | Sep 4, 1990 | Jan 16, 1990 | Sep. 4, 2007 | Rear-access trussed neck construction for stringed musical instruments. view patent. |
| 4,922,797 | May 8, 1990 | Dec 12, 1988 | May 8, 2007 | Layered Voice musical self-accompaniment system. view patent. |
| 4,649,785 | Mar 17, 1987 | Apr 15, 1980 | Mar. 17, 2004 | Musical timbre modification method. view patent. |
| 4,633,754 | Jan 6, 1987 | Feb 19, 1986 | Jan. 6, 2004 | "Rods"™ fret system for stringed musical instruments. view patent. |
| 3,868,880 | Mar 4, 1975 | Apr 3, 1974 | Mar 4, 1992 | Melody 4ths with reversed bass 5ths tuning. view patent. |
| 3,833,751 | Sep 3, 1974 | Feb 22, 1973 | Sep 3, 1991 | Belt hook and shoulder strap means of supporting stringed
instrument, melody 4ths with reversed bass 5ths tuning. view patent. |