Recognizer Conflicts [Office 2003 SDK Documentation]
Developers need to be aware of the possibility of recognition conflicts when building smart tags. First, it is quite possible that the same text is recognized by two different smart tag types. For example, "Greal" could be recognized as a CompanyName and ChemicalName types. In this instance, both smart tags will recognize this text and as a result, a user is presented with a cascading menu where action options from these two different smart tags are combined.
Secondly, if you have two recognizers installed (A and B) that attempt to recognize the same smart tag type (for example, StreetNames). Let's say A recognizes "123 Main Street" as a StreetName, while B recognizes "123 Main Street, Apt. 23" as a StreetName.
In a scenario like this where two sets of recognizers try to recognize an overlapping area (that is, "123 Main Street") as the same smart tag type, only one of these recognitions will be arbitrarily accepted. In Excel, this is not an issue because Excel only accepts recognitions that are the length of cell contents.
If two recognizers recognize the same string as the same smart tag type, the string is marked with the smart tag type and the property bags (for definition see Glossary) from both recognitions are merged. When two recognizers declare different values for the same property, one recognizer's properties will arbitrarily "win" over the other recognizer's properties. There are no set rules as to which recognizer will take precedence over another recognizer.