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• ctr:hasEffectiveDate, 
• doc:hasDateOfIssuance, hasDateOfIssuance 
• doc:hasExpirationDate   (maybe via fd:hasEndDate)

Make corp:hasDateOfIncorporation a subproperty of (a new property called hasCreationDate which is a subproperty of) fd:hasStartDate  

Recommended Additions

hasCreationDate a subproperty of hasStartDate

asOfDate a subproperty of hasDate

Used for credit reports.  Not necessarily the same as creation date, which could be later. Similar to but not quite the same as effectiveDate

datatype property for version indicator

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