Delta version must be 2.0 There must be a deltaxml:content-type attribute with one of the values 'full-context' or 'changes-only' Delta values must contain only the characters A,B,!, and = For a changes only document, all elements must have a deltaxml:deltaV2 attribute All child elements of an element with @deltaxml:deltaV2 containing '!=' must have a delta attribute An element that is a descendant of a non-modified element cannot have a delta attribute An element with delta A!=B must have at least one child with delta A, B or A!=B All elements representing attributes (i.e. child of deltaxml:attributes) must contain at least one deltaxml:attributeValue child For an element representing an attribute (i.e. child of deltaxml:attributes), the only child elements allowed are deltaxml:attributeValue elements All elements representing attributes (i.e. child of deltaxml:attributes) must be associated with a namespace A deltaxml:attributeValue element must be the grandchild of a deltaxml:attributes element A deltaxml:attributeValue element must contain only text node(s) A deltaxml:attributeValue element must contain either 0 or 1 text node A deltaxml:attributeValue element must have a deltaV2 value that expresses equality A deltaxml:attributeValue element must not have a sibling with the same deltaV2 value A deltaxml:attributes element must be the first child of its parent element The deltaxml:attributes element is always orderless A deltaxml:textGroup must contain at least one deltaxml:text child There should be no children in a deltaxml:textGroup that are not deltaxml:text elements A deltaxml:text element must contain only text node(s) A deltaxml:text element must contain either 0 or 1 text node A deltaxml:text element must have a deltaV2 value that expresses equality A deltaxml:text element must always be a child of a deltaxml:textGroup element