• On crypto exchange Bitfinex, traders are borrowing funds to set up bullish bets, one analyst said.
• Perpetual funding rates have flipped positive.
• Over-the-counter desks are witnessing demand for higher strike call options.

Activity on a crypto exchange known to host whales, or holders of large amounts of crypto, is defying concerns about bearish seasonal trends in bitcoin's (BTC) price.

Since 2009, bitcoin has dropped 4% on average in September, according to Bitcoinmonthlyreturn.com . In six of the past seven years, September has seen bears lead the action, so it's no surprise some observers are feeling defensive about the immediate price prospects for the largest cryptocurrency.

However, traders from the Bitfinex crypto exchange, which has a history of influencing market trends, seem to be setting up bullish bets.

Since Aug. 28, the number of margin longs on Bitfinex, which involve using borrowed funds to purchase BTC in the spot market, has increased by a net 3,000 BTC to nearly 64,350 BTC, according to data sources Greeks.Live and Coinglass . Meanwhile, the annualized interest rate charged on borrowed funds has surged to over 20% in the past 10 hours.

In other words, traders are borrowing money to buy more BTC, betting that this year, the cryptocurrency will defy its bearish September seasonality.

"Greens lending rates and long positions have always been an over-the-top indicator for bulls; the previous two major spikes were preceded by significant rises in rates and long positions," crypto block trading service provider Greeks.Live told CoinDesk in a Telegram chat. A green lending rates is an interest rate that's above zero.

Activity in bitcoin perpetual futures listed worldwide is also showing a renewed bullish bias. That's evident from the positive shift in the open interest-weighted global average funding rates. Positive rates indicate perpetual futures are trading at a premium to the spot price, indicating the dominance of bullish bets.

Meanwhile, over-the-counter (OTC) desks are witnessing renewed demand for bitcoin call options offering asymmetric payoffs during price uptrends.

"Options market has started to see a large number of block calls, accounting for 30% of the day's total and the whales are laying out long positions across the board," Greeks.Live said.

Elsewhere, call spread strategies were recorded on the OTC network Paradigm on Monday.

"OTM's [out-of-the-money] were in focus today, with an 80K/100K Dec call spread and an ETH 27 Dec/28 Mar calendar spread. There was also another noteworthy SOL print," Paradigm said in a Telegram broadcast.