Integration with Other Applications > Introduction to Windchill ESI > Integrating Windchill ESI with SAP > Supported Business Processes > Locking Documents in SAP and Enterprise Systems Integration
  
Locking Documents in SAP and Enterprise Systems Integration
A document that is locked by an online user is ignored when the following occurs:
Document version A exists in SAP
An SAP online user has the document “locked” (i.e., if the user is in the process of changing version A)
Windchill PDMLink sends a change to SAP via Windchill ESI to change document version A to version B
SAP creates version B by copying the most recently saved instance of version A and then makes the remaining changes