As covered in the Wikipedia article on Biblical canon, among the major branches of Christianity Protestantism has the smallest biblical canon, due almost entirely to a smaller Old Testament canon.
The various New Church or "Swedenborgian" denominations, however, have a considerably smaller canon for both the Old and New Testaments, as covered in this question: What writings are held as "biblical canon" by Swedenborgians?
Are there any other Christian churches or denominations whose biblical canon is smaller than the Protestant canon? If so, what books do they include in their canon, and what reasons do they give for their particular canon?