Comment 3 for bug 462949

The issue with using 'text to path' is known and a duplicate of bug #388257. You can try the workaround and use 'Path > Object to Path' for all texts before exporting to PDF, just don't save the SVG after the text is converted if you want to keep the text editable.

I can't reproduce the transparency of the light blue rectangle and the main 'Flowed text' objects I see in the PDF (using Apple's 'Preview' PDF viewer) with Inkscape 0.46+devel r22544 on OS X 10.5.8 using default PDF export settings. All text has the same color as in Inkscape (white, black) and the light blue background has no opacity in the new PDF.

I don't have your fonts installed though, but I have seen similar issues when text objects have been clipped (bug #446242 “Font rendering problem after converting fonts to paths at PDF export”: <https://bugs.launchpad.net/inkscape/+bug/446242>) and your SVG file has many now unused clipping paths in the <defs> section - maybe these are related issues.

The SVG file was created with 0.46 - which version did you use to export the PDF (see menu 'Help > About Inkscape' for version info)?