diff --git a/custom_signatures.yml b/custom_signatures.yml
new file mode 100644
index 0000000..21df082
--- /dev/null
+++ b/custom_signatures.yml
@@ -0,0 +1,108 @@
+#file: noinspection SpellCheckingInspection
+- bof: (?i)^576F726450726F0DFB000000000000000005985C8172030040CCC1BFFFBDF970
+  extension: .lwp
+  puid: x-fmt/340
+  signature: Lotus WordPro Document
+- bof: (?i)^00001A000(3|4|5)10040000000000
+  extension: '.123'
+  puid: aca-fmt/1
+  signature: Lotus 1-2-3 Spreadsheet
+- bof: (?i)(50|70)726F67(49|69)64[0-9A-F]{2,20}576f72642e446f63756d656e74
+  extension: .doc
+  puid: aca-fmt/2
+  signature: Microsoft Word Markup
+- bof: (?i)(50|70)726F67(49|69)64[0-9A-F]{2,18}457863656C2E5368656574
+  extension: .xls
+  puid: aca-fmt/3
+  signature: Microsoft Excel Markup
+- bof: (?i)75726e3a736368656d61732d6d6963726f736f66742d636f6d3a6f66666963653a657863656c
+  extension: .xls
+  puid: aca-fmt/3
+  signature: Microsoft Excel Markup
+- bof: (?i)^1a000003000014000000
+  extension: .ntf
+  puid: aca-fmt/5
+  signature: Lotus Notes Template
+- bof: (?i)^0300000041505052
+  extension: .adx
+  puid: aca-fmt/6
+  signature: Lotus Approach Index File
+- bof: (?i)^1a000004000029000000
+  eof: (?i)bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
+  extension: .nsf
+  operator: AND
+  puid: aca-fmt/8
+  signature: Lotus Notes Database
+- bof: (?i)4D696E644d616E61676572
+  extension: .mmap
+  puid: aca-fmt/4
+  signature: MindManager Mind Map
+- bof: (?i)010000002E010000(43|03)000000
+  extension: .id
+  puid: aca-fmt/7
+  signature: ID File
+- bof: (?i)474946383961
+  extension: .gif
+  puid: fmt/4
+  signature: GIF 1989a
+- bof: (?i)010690080004000000000001000100010790060008000000E404000000000000E80001088007001800000049504D2E4D6963726F736F6674204D61696C2E4E6F746500310801
+  extension: .dat
+  puid: aca-fmt/9
+  signature: Microsoft email attachments archive (winmail)
+- bof: (?i)010690080004000000000001000100010790060008000000E404000000000000E800010
+  extension: .dat
+  puid: aca-fmt/9
+  signature: Microsoft email attachments archive (winmail)
+- bof: (?i)^789F3E22
+  extension: .dat
+  puid: aca-fmt/9
+  signature: Microsoft email attachments archive (winmail)
+- bof: (?i)41636365737356657273696F6E.{0,1024}30362E
+  extension: .mdb
+  puid: aca-fmt/10
+  signature: MS Access 95
+- bof: (?i)41636365737356657273696F6E.{0,1024}30372E
+  extension: .mdb
+  puid: aca-fmt/11
+  signature: MS Access 97
+- bof: (?i)410063006300650073007300560065007200730069006F006E.{0,2048}300038002E00
+  extension: .mdb
+  puid: aca-fmt/12
+  signature: MS Access 2000
+- bof: (?i)410063006300650073007300560065007200730069006F006E.{0,2048}300039002E00
+  extension: .mdb
+  puid: aca-fmt/13
+  signature: MS Access 2002/3
+- bof: (?i)^000100005374616E64617264204A65742044420000000000
+  extension: .mdb
+  puid: aca-fmt/14
+  signature: MS Access database unspecified version (Jet 3 DB)
+- bof: (?i)^000100005374616E64617264204A65742044420001000000
+  extension: .mdb
+  puid: aca-fmt/15
+  signature: MS Access database unspecified version (Jet 4 DB)
+- bof: (?i)000100005374616E646172642041434520444200
+  extension: .mdb
+  puid: aca-fmt/16
+  signature: MS Access database unspecified version (ACE DB)
+- bof: (?i)00A0E150E161BA2A6AB1A2A2FA5A9B5A7B5D90F1723131F2B0F17234F57639CA4A9A0A8ADA4A8AD161A390D1137A5A9B5A4A8ADB2B6DCBDBDF42B2F55C8CCD8C7CBD0D3D7FDC2C2F90
+  extension: .map
+  puid: aca-fmt/17
+  signature: MapInfo MAP file
+- bof: (?i)^504B0304{26}6D696D65747970656170706C69636174696F6E2F766E642E6F617369732E6F70656E646F63756D656E742E74657874
+  extension: .odt
+  puid: aca-fmt/18
+  signature: OpenDocument Text (unspecified version)
+- bof: (?i)41007000700072006F0061006300680044006F006300
+  extension: .apr
+  puid: aca-fmt/19
+  signature: Lotus Approach View File
+- bof: (?i)^217461626C650D0A2176657273696F6E.{20,512}446566696E6974696F6E205461626C65
+  extension: .tab
+  puid: aca-fmt/20
+  signature: MapInfo TAB file
+- bof: (?i)^bWltZXR5cGVhcHBsaWNhdGlvbi92bmQub2FzaXMub3BlbmRvY3VtZW50LnNwcmVhZHNoZWV0
+  extension: .ods
+  plain_bof: mimetypeapplication/vnd.oasis.opendocument.spreadsheet
+  puid: aca-fmt/21
+  signature: OpenDocument Spreadsheet (unspecified version)