A total of 62K Bitcoin (BTC) options are set to expire this Friday, and this is equivalent to $830 million in open interest. These massive numbers fail to reflect the fact that 58% of these options are now deemed worthless.

As we approach the expiry date, call (buy) options above the current level begin to depreciate very fast. It is not worth paying $20 for the opportunity to buy BTC at $14.5K on Friday morning. Therefore, rolling options to the next month is not that helpful.

October BTC options pricing. Source: Deribit

With less than 48 hours to October's expiry, call (buy) options above $14.5K and above face slim odds. The same can be said for the $11.5K put (sell) options which are currently trading below $10 apiece.

Deribit leads with a 70% market share of the options that are still worthy. Currently, there are $134 million worth of call (buy) options from $11.5K to $13.5K, stacked against $45.5 million in put (sell) options from $12.5K to $14.5K. Thus, bulls favor bears by a ratio of 3:1.

Chicago Mercantile Exchange (CME) holds a 26% market share among the October BTC options that still count. The call (buy) options near the current market level totals $72 million, whereas the put (sell) is less than $1 million. This movement is not unlike past expiries as CME option traders are usually extremely bullish.

Therefore, there's currently a $160 million imbalance favoring bulls on BTC option markets. This is a relevant number considering the expiry happens at a set time. OKEx and Deribit options and futures are set to expire at 8:00 AM (UTC) on October 30, and the CME a few hours later at 4:00 PM (UTC).

Futures open interest typically falls near expiry

Many traders believe that Bitcoin futures $5.4 billion open interest is also set to expire on Friday. Most of those contracts are either perpetual (inverse swap) or set for a later date.

This time around, CME leads with $360 million open interest for October, but there's a catch. This notional will drastically reduce ahead of expiry as traders move their positions for upcoming months. As proof of this movement, the CME’s outstanding October open interest was cut by $130 million yesterday.

No matter how big an investor’s win or loss is, rolling over the position for the next expiry is viable. Unlike options markets, futures contracts don't devalue nearing their last trading day.

Futures margin is adjusted daily, meaning, the contract buyer (long) gets paid by the seller (short) when Bitcoin trades up, and the opposite happens if BTC price closes down. Both sides can benefit from rolling over their positions, as long as there's enough margin to maintain it.

For professional traders, futures premium is the most useful indicator to gauge how bullish or bearish those investors are. At the time of writing, OKEx leads the remaining exchanges with $69 million set to expire on Friday, followed by Huobi's $23 million.

This indicator is known as basis, and it usually ranges between a 5% to 15% annualized rate. Whenever the premium is positive, the market is characterized as being in contango. Meanwhile, levels below 5% indicate modest bearishness.

A negative future contracts premium is highly unusual and is usually related to liquidity issues.

Bitcoin 1-month futures annualized premium. Source: Skew

As the above chart shows, investors were very bullish in August, as the 1-month futures contract traded with a 25% or higher premium. That was caused by a 30% Bitcoin hike from $9.1K to $11.9K.

The basis indicator currently stands near 14%, on the verge of a very bullish zone. One must factor in that any leveraged bullish position opened in the past six months is currently gaining.

Bitcoin futures aggregate open interest. Source: Skew

Meanwhile, BTC futures open interest more than doubled to $5.4 billion from $2.6 billion back in April. Therefore, it is safe to conclude that investors are well prepared to defend the current $13K support level.

Both derivatives contracts are supporting the market’s current strength. Aside from the $160 million options expiry imbalance, futures contract buyers are holding a comfortable position.

Furthermore, as Bitcoin spiked from $11.3K just twelve days ago, short-sellers have been suffering and watching their balances decrease every day.

As for Friday's expiry, some added volatility is to be expected as usual, but as far as the futures premium can tell, it’s unlikely that the bears will have a chance to re-establish control of the markets.

The views and opinions expressed here are solely those of the author and do not necessarily reflect the views of Cointelegraph. Every investment and trading move involves risk. You should conduct your own research when making a decision.