The shares of different companies related to bitcoin (BTC) have experienced a significant rise, amid the appreciation of the digital currency to its highest levels in 18 months.

Among them, the shares of the cryptocurrency exchange Coinbase (COIN) stand out for registering an increase of 79% in the last two months. Similarly, both bitcoin mining company Cleanspark (CLSK) and digital asset investment manager Galaxy (GLXY.TO) rose 72%.

In addition to shares of companies in the industry, other traditional instruments of exposure to the digital currency also rose. For example, the bitcoin investment fund “GBTC”, from Grayscale, with a rise of 74%. This can be seen in the following graph provided by the investment and analysis company Matrixport.

As the bitcoin bull market expands, traditional investors buy regulated instruments in their industry. This way, they can gain upside exposure. The industry's stock performance shows pent-up demand from traditional investors seeking exposure to BTC. In turn, it reflects that they need as an alternative a bitcoin spot ETF listed in the United States.

In this sense, if ETFs are approved in the American powerhouse, the valuation of companies in the industry could be at risk of falling, since investors could gain exposure to such products. However, it is possible that, if these are in high demand, the shares of related companies, such as Coinbase, will benefit as revenue projections could change dramatically if the ETFs are approved. That's because BlackRock, the giant manager requesting one, has indicated to the SEC its desire to collaborate with Coinbase's custody arm.

It's also interesting that historically bitcoin has risen more than 12% in December, aligning with its early 2023 goal of reaching $45,000.Amid the bullish trend that bitcoin has experienced this year and with the possible approval of ETFs in January or sooner, $45,000 now seems likely.