===Patent Number Cleanup===
The goal is to only have assignment records on utility patents. The patents in ptoproperty include alphanumerics , which represent reissue and design patents as well as mistakes in the data input. Additionally, the documentids include application numbers or ids and publication numbers. The ptoproperty table stores the patent ids as character strings.
First the duplicates were dropped from the ptoproperty table creating ptoproperty_cleaned.
SELECT COUNT(*) FROM ptoproperty WHERE documentid LIKE 'D%';
--1128247
Finally, all letters were removed from the data, resulting in the final version of ptoproperty_cleaned.
In order
===Ptotracking Tables===