Here is how the Grayscale Trust helps fuel the #Bitcoin bubble. First Grayscale spends lots of money on @CNBC running non-stop ads pumping Bitcoin to investors. CNBC then returns the favor by constantly featuring pro-Bitcoin guests on air, who make pie-in-the-sky price forecasts.

At the same time CNBC keeps Bitcoin skeptics off its air. This constant on-sided pumping results in GBTC trading at a large premium to its NAV, allowing Grayscale to create new shares of GBTC that it promptly sells into the market for an instant profit.

It then uses the cash it receives from selling GBTC shares to buy even more Bitcoin in the market, putting additional upward pressure on Bitcoin's price. Grayscale then uses some of the profits earned by selling its own shares at a premium to fund even more commercials on CNBC.

But since its own buying has pushed up the price of Bitcoin, more buyers are suckered into the market to get in on the action. This increases the effectiveness of its ad campaign, as Bitcoin's price rise validates the forecasts and rewards GBTC buyers with quick paper gains.

This process can repeat until the bubble pops, and demand for GBTC dries up. Once GBTC speculators want out, GBTC shares will trade at a discount. That means Grayscale will stop issuing new shares, which means it will no longer be buying more Bitcoin in the market.

With Bitcoin's biggest buyer sidelined, the price of Bitcoin will fall even faster, causing even more GBTC holders to want out, further widening the discount to NAV. If Grayscale wants to close that gap it will have to sell Bitcoin and buy back shares, pushing Bitcoin even lower.

But reducing AUM also lowers the management fees. So GBTC may not sell Bitcoin to close the discount, but only sell what is needed to cover the steep 2% annual management fee. Those sales alone could result in Grayscale going from the biggest Bitcoin buyer to the biggest seller.