In Cramer's perspective, the reasons why the two companies had early lockup expirations were very different. Therefore, the stocks should be treated differently.
Typically, when a company goes public, the insiders will agree with the bankers underwriting the deal that they will not sell their shares for a set period. That period is usually six months following the IPO.
In the case of GoPro, CEO Nick Woodman and his wife, Jill, announced they were establishing a $500 million charitable foundation to be funded via the transfer of some of their position in GoPro shares. So, the lead underwriter agreed to release the Woodmans' new charitable foundation from its lockup restriction for about 5.8 million shares.
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"Giving half a billion dollars to charity is a wonderful thing to do, no question, but this show is about helping individual investors try to make money. And having insiders dump that much stock on the open market was very bad news for GoPro's shareholders," the "Mad Money" host said.
Meanwhile, Fitbit's early lockup release was very different. Two and a half weeks ago, when Fitbit reported, it announced that its lead underwriter had granted Fitbit an early lockup release so the company could sell 21 million shares via a secondary offering.
Ultimately, the figure was reduced to 17 million, with 14 million from existing shareholders, and 3 million from new stock that Fitbit was selling to raise capital.
So, in this case, Fitbit itself sold stock to raise money to invest in its business. A major rationale for the secondary offering was to create an orderly process for the company's venture capital shareholders to sell stock. CEO James Park also said insiders and sellers taking part in the secondary would have to agree to an additional 90-day lockup on selling the rest of their shares.
Fitbit's stock was obliterated, including a hideous 12 percent decline last Friday when the secondary offering priced at $29.
"Will it continue to get hammered like GoPro did? I think the short answer is no, because despite the similarities, Fitbit has a lot more going for it than GoPro did at this time last year," Cramer said.
Cramer thinks it would be a mistake to dismiss Fitbit as the next GoPro. Fitbit's numbers are much stronger, with better prospects and a cheaper stock. That means when the full lockup on insider selling ends in one month, Cramer wants investors ready to buy Fitbit into any additional weakness.