No – Score Exchange can accept PDF files or Sibelius files. Every scoring application we have ever seen has the ability to produce a PDF file.
If you do own Sibelius, then Score Exchange can automatically extra information from your scores such as the instrumental parts. This means that if you have a Sibelius file of your music, you should upload the Sibelius file – don’t convert it into a PDF first.
You can use a copy of Sibelius that is owned by someone else, such as your School or College to create your scores. Sibelius is a music notation program. You can find out more at www.sibelius.com.