H04M 1/50
By generating or selecting currents of predetermined frequencies or combinations of frequencies
Official title: by generating or selecting currents of predetermined frequencies or combinations of frequencies
H04M1/50 (By generating or selecting currents of predetermined frequencies or combinations of frequencies) appears on 149 US grants and 72 published applications in this corpus.
Search patents in H04M- Granted patents
- 149
- Published applications
- 72
- Assignees
- 99
- Inventors
- 247
- Latest grant
- 27 Jan 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 8 | 0 |
| 1977 | 8 | 0 |
| 1978 | 4 | 0 |
| 1979 | 4 | 0 |
| 1980 | 1 | 0 |
| 1981 | 1 | 0 |
| 1982 | 7 | 0 |
| 1983 | 5 | 0 |
| 1984 | 4 | 0 |
| 1985 | 4 | 0 |
| 1986 | 3 | 0 |
| 1987 | 3 | 0 |
| 1988 | 3 | 0 |
| 1989 | 2 | 0 |
| 1990 | 4 | 0 |
| 1991 | 3 | 0 |
| 1992 | 1 | 0 |
| 1993 | 1 | 0 |
| 1994 | 0 | 0 |
| 1995 | 3 | 0 |
| 1996 | 2 | 0 |
| 1997 | 1 | 0 |
| 1998 | 7 | 0 |
| 1999 | 7 | 0 |
| 2000 | 1 | 0 |
| 2001 | 2 | 2 |
| 2002 | 5 | 4 |
| 2003 | 6 | 8 |
| 2004 | 5 | 9 |
| 2005 | 4 | 4 |
| 2006 | 4 | 5 |
| 2007 | 3 | 6 |
| 2008 | 1 | 7 |
| 2009 | 1 | 3 |
| 2010 | 2 | 0 |
| 2011 | 3 | 2 |
| 2012 | 5 | 3 |
| 2013 | 7 | 6 |
| 2014 | 3 | 1 |
| 2015 | 2 | 2 |
| 2016 | 0 | 2 |
| 2017 | 1 | 1 |
| 2018 | 1 | 2 |
| 2019 | 3 | 2 |
| 2020 | 1 | 1 |
| 2021 | 2 | 0 |
| 2022 | 0 | 0 |
| 2023 | 0 | 0 |
| 2024 | 0 | 1 |
| 2025 | 0 | 0 |
| 2026 | 1 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Property modification during communication session27 Jan 2026US 12,537,899 B1Zoom Communications, Inc.
- Systems and methods for content delivery and management21 Sep 2021US 11,126,394 B2Lisnr, Inc.
- Access control and validation using sonic tones27 Jul 2021US 11,074,033 B2Lisnr, Inc.
- Mobile terminal for automatically making a telephone conversation using artificial intelligence11 Aug 2020US 10,742,808 B2LG Electronics Inc.
- Mobile terminal3 Sep 2019US 10,404,857 B2LG Electronics Inc.
- Communication Session Modification for External Bypass Integration16 Apr 2026US 2026/0106938 A1Zoom Communications, Inc.
- Telephone signal processing24 Oct 2024US 2024/0357040 A1Sycurio Limited
- Telephone signal processing5 Mar 2020US 2020/0076953 A1Semafone Limited
- Mobile terminal4 Jul 2019US 2019/0208057 A1LG Electronics Inc.
- Mobile terminal23 May 2019US 2019/0158665 A1LG Electronics Inc.
Most cited
By later US patents
- Method and apparatus for telephonically accessing and navigating the internet268US 5,953,392 ANetphonic Communications, Inc. · 1999
- Information storage device for storing personal identification information232US 5,825,871 ASmart Tone Authentication, Inc. · 1998
- Personal digital assistant module adapted for initiating telephone communications through DTMF dialing231US 5,522,089 ACordata, Inc. · 1996
- System and method using personal identification numbers and associated prompts for controlling unauthorized use of a security device and unauthorized access to a resource230US 5,745,555 ASmart Tone Authentication, Inc. · 1998
- Method and apparatus for the secure communication of data178US 5,583,933 A1996