Disclosed herein is a streaming distributing device including: a content fragment generating section configured to generate a fragment storing data of a content to be distributed by streaming, the fragment being defined by an MP4 file format; and a subtitle fragment generating section configured to generate a fragment storing a TTML (Timed Text Markup Language) document instance relating to a subtitle to be displayed in the content, the fragment being defined by the MP4 file format, wherein the subtitle fragment generating section adds, to header information of the fragment, instance classification distinguishing information for distinguishing whether the TTML document instance stored in the fragment is a TTML document instance specifying a rendering context relating to the subtitle.