Can one lay a claim on a database structure? Does this constitute of intellectual property? 

Scenario: 

Developer X is handing over a project he did for Client Y. Developer refused to give up the scripts, saying all coding is their intellectual property. So All we got was the database dump. 

I have used some scripts , reverse engineered the process and introduced some simple CRUD files and can now "administer" the content. Developer X is not bitching, that we used their database structure. 

Im miffed. Is this even possible? how then would I have gotten the data? Does it change the intellectual property "ginene" if I change the names of the tables? 

~ #shocked  
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