Finders keepers losers weepers doesn't have any relevance after age 8, sorry.
There are thousands of rules outlining what you find and how t can be used.
If you found software in a dumpster that doesn't mean it is yours now. If you throw out a piece of paper with your credit card number on it, someone is free to dig in your trash and use it, this does not mean it is legal use though. It is still a criminal offence, you ca have the information but are not allowed to use it.
In the case of software, there are several different licencing techniques used, none of them will allow unauthorized installation and use of the software.
As 'generalist' said, these could be boxes from a 2000 node install at a company that is using the current and legal licences, your useage would be illegal. SELLING the software for your own profit would most likely land you in jail.
One post suggested reporting you to the BSA, I know the Boy Scouts of America would be pissed and would probably report you to the Business Association of America.
Lets assume that you sold a copy to an end user with some questions or a support request. That person has bougt tha software from you and it comes in a box with XXXXX's name on it. They then look to that company for support or an upgrade and it is found to be an illegitimate software licence. The company that created the software will soon track you through Ebay and you are facing legalities, not from some end user but a VERY angry software designer/manufacturer, hope you have money for the lawyers because the creators probably do.
Your best bet, stick to moldy sandwiches and used papertowels, leave unopened software alone, you will inevitably get nailed by someone down the line and NO you have no legal position in this matter at all.
Stick to binning in residential areas, you'll have less problems.