How do you tell if an invention was ever “patent pending?” and has since been denied?

AVVO had an interesting discussion on the topic of How do you tell if a patent was ever “pending?” and has since been denied
? Other patent lawyers had already suggested going to the USPTO.GOV website and searching for patents and applicaitons by the company or person you are interested in. Of course only issued patents and published patent applications are searchable. Patent applications generally publish 18 months after the filing date. My suggestion was to search the assignment database at the USPTO.GOV website. There you can search patents and published patent applications by assignees and assignors.
As for determing whether a patent application has been denied, you should be able to see published patent applications in public pair at the USPTO.GOV website, and look up their prosecution history and determine if the patent application issued, or was abandoned.