is this a known soft sub format?

[smok3]

I have some subs that look like this:

00:10:12:13 00:12:26:24
text text text text text
text text text

00:12:27:13 00:12:32:24
text text text text text
text text text

where the numbers are obviously an in and out timecode (25fps version). So is this some known format with some name?

[bigotti5]

former Adobe Encore format

[Nikse555]

Could also be "Avid Caption"... a .txt file
(Subtitle Edit recognizes it as this...)