XML Data Binding with Invalid XML documents

You can use the SerializationConetxt to allow you to read or write XML that is not valid against the XSD schema:

IgnoreUnknownAttributes - Cause the parser to ignore attributes that are not present in the schema. Default = false.
IgnoreUnknownElements - Cause the parser to ignore elements that are not present in the schema. Default = false.
IgnoreMissingMandatoryElements - Causes the parser to ignore mandatory elements that are missing in the XML document. Default = false.
IgnoreMissingChoice - Causes the parser to ignore empty choices (ones that should contain a valid element). Default = false.
IgnoreInvalidCollectionCounts - Causes the parser to accept collections with the wrong number of elements in them. Default = false.
IgnoreNamespaces - Causes the parser to accept items with the wrong namespace. Default = false.
NoOptionalAttributeDefaultOutput - Causes the parser to omit optional attribute default values from output XML document. Default = false.
WriteTypeAttribute Determines if xs:type attribute is written out for derived elements. Default = true.

XML Data Binder Help:

Controlling Serialization Validation Example Code: