Cramer has seen this transformation of private company innovation particularly in the travel industry. Long gone are the days when companies sending their employees on a business trip book the hotels and pay for everything later.
These days everything is paid for in advance. People go on Trip Advisor for reviews, and then Expedia for booking. Private companies like HotelTonight will even help hotels fill their rooms by offering customers lower prices as the night goes on.
"I think it is my job to bring you these ideas before they IPO, like HotelTonight, because if I wait too long and you don't find out about them until they're about to go public, you will end up having to compete against huge funds that have gotten their orders in early so they will get top priority over you," Cramer said.
Cramer also reminded investors that when he highlights a private company, he often lacks the kind of financials he would normally require before it appears on "Mad Money." He is also not sure if or when the company will make itself public. Thus he remains highly skeptical of the huge valuations from many of the companies, or so-called unicorns, given how difficult the public market has become.
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Nevertheless, Cramer has seen a dramatic increase in enthusiasm for some of these private companies. His skepticism was sorely tested when he heard about the growth that these companies have and the prospects that await them.
With this in mind, Cramer encouraged investors to pay attention to the trends happening not only in the public market, but the private one, too. This way you can make up your mind about the company well ahead of when they might come public and be fully prepared to take action if necessary.
"No matter what, I want you to see the future before it happens, so you can be a better investor," Cramer said. (Tweet this)