E04F 11/04
Movable stairways
Official title: Movable stairways, e.g. of loft ladders which may or may not be concealable or extensible (ship ladders B63B; stairs for aircraft B64F; escalators or moving walkways B66B)
E04F11/04 (Movable stairways) appears on 173 US grants and 165 published applications in this corpus.
Search patents in E04F- Granted patents
- 173
- Published applications
- 165
- Assignees
- 73
- Inventors
- 270
- Latest grant
- 8 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 0 | 0 |
| 1978 | 2 | 0 |
| 1979 | 2 | 0 |
| 1980 | 0 | 0 |
| 1981 | 2 | 0 |
| 1982 | 2 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 4 | 0 |
| 1986 | 2 | 0 |
| 1987 | 3 | 0 |
| 1988 | 1 | 0 |
| 1989 | 1 | 0 |
| 1990 | 1 | 0 |
| 1991 | 1 | 0 |
| 1992 | 2 | 0 |
| 1993 | 4 | 0 |
| 1994 | 0 | 0 |
| 1995 | 2 | 0 |
| 1996 | 1 | 0 |
| 1997 | 2 | 0 |
| 1998 | 0 | 0 |
| 1999 | 1 | 0 |
| 2000 | 1 | 0 |
| 2001 | 0 | 0 |
| 2002 | 2 | 2 |
| 2003 | 1 | 1 |
| 2004 | 2 | 3 |
| 2005 | 3 | 6 |
| 2006 | 3 | 7 |
| 2007 | 2 | 8 |
| 2008 | 3 | 5 |
| 2009 | 3 | 5 |
| 2010 | 6 | 7 |
| 2011 | 4 | 7 |
| 2012 | 5 | 8 |
| 2013 | 8 | 6 |
| 2014 | 4 | 3 |
| 2015 | 8 | 9 |
| 2016 | 11 | 6 |
| 2017 | 8 | 2 |
| 2018 | 7 | 13 |
| 2019 | 11 | 5 |
| 2020 | 7 | 7 |
| 2021 | 5 | 11 |
| 2022 | 7 | 10 |
| 2023 | 5 | 10 |
| 2024 | 5 | 9 |
| 2025 | 11 | 10 |
| 2026 | 7 | 5 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Foldable stair assembly8 Sep 2026US 12,728,899 B2Safesmart LLC
- Portable staircase21 Jul 2026US 12,687,023 B1
- Door and retractable ladder assembly23 Jun 2026US 12,662,821 B1
- Box structure building partition12 May 2026US 12,624,591 B2Fakro Pp Sp. Z O.O.
- Box construction lock24 Feb 2026US 12,559,983 B2Fakro Pp Sp. Z O.O.
- Folding staircase10 Sep 2026US 2026/0266060 A1Calbah Industries Pty Ltd
- Attic stairs7 May 2026US 2026/0125907 A1Sj industries Inc.
- Robot-deployable accessibility system19 Mar 2026US 2026/0078586 A1United Kingdom Atomic Energy Authority
- Modular building platform and assembly method thereof8 Jan 2026US 2026/0009220 A1
- Folding staircase8 Jan 2026US 2026/0009230 A1Morryde International, Inc.
Most cited
By later US patents
- Insulating enclosure for disappearing stairway44US 4,281,743 A1981
- Attic hatchway insulating cover43US 4,658,555 A1987
- Multipocket means for holding insulation to prevent heat loss through an attic stairwell38US 5,628,151 A1997
- Foldable or retractable ladder for mounting in a ceiling37US 4,541,508 A1985
- Insulating system for attic stairs and the like37US 5,475,955 A1995