The recently introduced "trans-fee mining" revenue model is starting to change the cryptocurrency exchange landscape, despite some criticism of the method from industry insiders.

According to CoinMarketCap, two exchanges have just shot to the top of the 24-hour trading volume rankings after rolling out trans-fee mining for users.

The data shows that 24-hour trading volume on Singapore-based CoinBene is now almost $2 billion, while on Hong Kong's Bit-Z the figure is close to $1.5 billion – both well ahead of the $1 billion in volume posted by the previous leader, Binance.

First featured by FCoin, a new exchange launched in May by a former chief technology officer of Huobi, the trans-fee mining model sees crypto exchanges issue their own tokens as a means to incentivize users to trade on the platform.

In Bit-Z's example, according to its white paper, the platform plans to produce its BZ token with a capped total issuance of 300 million. For every transaction fee a user pays to Bit-Z in the form of either bitcoin or ethereum, the platform will reimburse the user 100 percent of the value in its token.

Based on announcements from the two companies, CoinBene launched its offering on June 18, while Bit-Z started on Monday. Notably, the sudden spike in trading volume seen as a result pushed them to become the top two global platforms within days of their respective token issuances.

As previously reported by CoinDesk, one of the controversies associated with the nascent model is that it could incentivize users to create fake transactions using automated bots in an effort to obtain the tokens issued by exchanges.

After FCoin's trading volume first spiked in the last month, the Chinese cryptocurrency media, as well as Binance, also weighed in with allegations that the model is, in essence, an initial coin offering (ICO) and that the token's price could be manipulated by exchanges.

Zhao Changpeng, founder and CEO of Binance, further questioned whether the model is sustainable in the long-term.

Related news indicates that the criticisms may not be deterring exchanges from adopting trans-fee mining, however. BigONE – an exchange backed by Chinese crypto investor Li Xiaolai – is also moving to adopt the model, according to the company's website.

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