The issue of company or organization record duplication is a problem of many career web-sites. It seems that Stack Overflow Jobs (SOJ) doesn't address this problem systematically.
Possible approaches:
On a page of every organization there is a «Flag spam» link, why not to add a button «Report a duplicate»? That way users could report about potential company duplicates and assist the SOJ team to merge the duplicate pages.
To implement ability not only report about duplicates but also to edit a company data, just like in Google Maps, where a user can add, edit, or remove item. In our case, it should be the ability to edit company meta-data, e.g. logo, legal status, website, HQ, number of employees, annual revenue, etc.
Important:
Please, try to keep the most updated logo version at the best quality when merging the companies. There is nothing worse than looking at outdated pixelated logo of the company at its profile.
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