Image source: Pinnacle Entertainment.

What: If you checked your brokerage account at the beginning of May, you may have been surprised to see shares of Pinnacle Entertainment Inc. (NASDAQ: PNK) down 69% from a month earlier. Don't worry, the company didn't fall apart, but it did make a transaction that will change your portfolio.

So what: The change in Pinnacle Entertainment's share price stems from its sale of real estate assets to Gaming and Leisure Properties (NASDAQ:GLPI). As part of the sale, a "new" Pinnacle Entertainment was formed and shareholders got one share in the new company (which is what trades on the market today). The "old" company was acquired by Gaming and Leisure Properties and shareholders were given 0.85 shares of the company for each share of Pinnacle. As a result, each share of the old Pinnacle Entertainment turned into one share of the new Pinnacle Entertainment and 0.85 shares of Gaming and Leisure Properties.  

Now what: When it was all said and done, if you held shares of Pinnacle Entertainment at the beginning of April, you actually had more value by the end of the month given where stock prices ended up. It just took a convoluted number of transactions to get there.

The decision investors need to make now is what they want to keep. Pinnacle Entertainment is now a gaming operations company with very little real estate, and Gaming and Leisure Properties is a real estate investment trust with no real gaming exposure. Depending on what your investment thesis was on Pinnacle Entertainment, it might be time to adjust your portfolio.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.