I've noticed a couple of my original records incorrectly merged with other records in WorldCat. One can report the error, and in my case, my records were restored. 

Catalogers should be aware of the Duplicate Detection and Resolution (DDR) software currently running in WorldCat/OCLC. 

https://www.oclc.org/services/metadata/quality/ddr.en.html

Here is a presentation (with powerpoint slides to view) that help explain how to catalog defensively to prevent your original records from being incorrectly merged with other records. Really, that's a thing - cataloging defensively.

http://www.oclc.org/en-US/events/2010/cataloging-defensively-20101028.html