Imagine a company sold a 10% stake in one of its assets to a 3rd party for $100 million. It would be fair to assume that the asset is worth $1 billion.
If that company had 200 million shares issued, and were trading at a price of $4/share, then its market capitalization would be $800 million.
Does that mean the share is undervalued, because its market cap is only $800 million but yet by outsiders/a 3rd party transaction, one of its assets alone is worth $1 billion? Hence, the share price should be worth at least $5/share? Else, what am I missing?