It seems like forever since the Winklevoss brothers, famous for their conflict with Mark Zuckerberg over the idea for Facebook, filed with the SEC to bring a bitcoin ETF to the market (actually it’s been about 3 ½ years). The two sides have gone back and forth on the Winklevoss Bitcoin Trust ETF (COIN) proposal and the SEC has extended the deadline to make a final ruling a number of times for any number of reasons. But the law says that there is a limit of 240 days for extensions from the initial submission date, which was June 2016. That puts the deadline for the SEC to make a decision at March 11.Two other bitcoin ETF filings, the Bitcoin Investment Trust and the SolidX Bitcoin Trust have seen their approvals delayed as well.I believe that the SEC will not give their approval for the Bitcoin ETF. While the approval of a bitcoin ETF is probably inevitable, I think the SEC is uncomfortable with giving the go-ahead right now for a few reasons. Security - While the bitcoin industry has come a long way to address the security of the exchanges and protect against illegal activity, I think the SEC won’t be satisfied that it’s come far enough. With so many business and government agencies continuing to fall victim to piracy and cybertheft, the SEC will want additional measures in place before opening the bitcoin market to the masses.Liquidity - China just cracked down on the cryptocurrency markets which cut down on trading frequency significantly. I think there’s probably enough liquidity available that it won’t be a huge concern but lack of liquidity can really harm investors.Volatility - Since its debut, the price of bitcoin has gone from under $100 to nearly $1200, back to under $200 and up to its current level of around $1000. That’s all in just a few years. Volatility tends to lead to panicky investors and panicky investors tend to lose their money. Will the SEC be OK with this?Shareholder Protection - The SEC’s ultimate job is to protect shareholders. Bitcoin isn’t overseen by the government and that lack of control may make the SEC uneasy. I think the government will want to make extra sure that all the i’s are dotted and t’s are crossed before approving a bitcoin fund since tens of millions of dollars are likely to flow into this product very quickly. If something bad happens right off the bat, things could get ugly.I think the Winklevoss Bitcoin ETF doesn’t get its approval from the SEC but it’ll just be a matter of time before one of the bitcoin ETFs eventually gets OK’ed.What do you think? Do you think the Bitcoin ETF will finally get approved? Would you invest in it yourself? Vote or post in the comments below. Requires signing in. That’s easy: Just use your Facebook, Twitter, LinkedIn or StockTwits credentials.