On Wednesday, before the stock market opened in New York, Goldman Sachs analyst Patrick Archambault upgraded shares of Tesla.

Archambault put a "Buy" rating and a $250 a share price target on the stock because of what he sees as the market's failure to "fully [capture] the company's disruptive potential."

On Wednesday, after the market closed in New York, Tesla said it would sell $2 billion worth of stock, $1.4 billion of which would be issued by the company.

Tesla CEO Elon Musk would sell $600 million worth of stock to meet a tax obligation related to his buying even more Tesla stock. It's complicated. You can read about that here.

Running the book for that new stock offering? Morgan Stanley and ... Goldman Sachs.

Now if you believe that banks — and specifically Goldman — are bad actors, this sort of deal makes sense. You might, in this scenario, say, "Well, of course: Goldman says nice things about Tesla and then Tesla does a nice thing for Goldman."

This would, however, be a breach of what the banks call a "Chinese Wall," or a separation of various divisions that could come into conflict one another.

Research and investment banking are examples of divisions that could create a conflict of interest and between which there exists said wall — meaning that research analysts don't know who investment banks are doing deals with and investment banks don't know what analysts think of companies outside of published research.