Changes

Patent start date end date project <p>Patent Maintenance Fee Schedule:</p><p>https://www.uspto.gov/learning-and-resources/fees-and-payment/uspto-fee-schedule#Patent Maintenance Fee</p> <p>Fees need to be paid 3.5 ~4, 7.5 ~8, and 11.5 ~12 years after grant</p><p>After some time, t, patents are valid from the grant date to 20 years after the application date.</p><p>Before t, patents are valid from the application date to 18 years before the grant date.</p> '''<p><strong>I don’t don&rsquo;t know what happens when people don’t don&rsquo;t pay maintenance fees.'''</strong></p><p>There is enough information in the <strong>patent </strong>&nbsp;and <strong>feestatus </strong>table to create a <strong>patentStartdateEnddate </strong> table.</p> <p>Table we want to make:</p>  <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Table "public.patentstartdateenddate"</p><p>Column &nbsp; | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Type &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; | Modifiers </p><p>---------+--------------------+-----------</p><p>patent &nbsp; | character varying | </p><p>start &nbsp; &nbsp; &nbsp;| date &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; | </p><p>end &nbsp; &nbsp; &nbsp; | date &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;| </p><p>&nbsp;</p><p><strong>Methodology:</strong></p><p>Take the patentID from the ''patent'' table.</p><p>Check if a fee has been paid within a certain date range using the ''feestatus'' table.</p><p>The date range will have to be determined by learning about the rules around maintenance fees.</p>