Global wash trading on cryptocurrency markets was down by more than 35% in September, according to the latest surveillance report from the Blockchain Transparency Institute (BTI).

Kraken, Poloniex, Coinbase and Upbit are still the “cleanest” platforms

According to the report, global wash trading was reduced by 35.7% among the exchanges on the institute’s top 40 listings.

Wash trading refers to a practice where sell and buy orders are simultaneously placed on the same asset to artificially inflate trading volumes while giving the impression that the asset is more in demand than it actually is. The practice is illegal on regulated exchange platforms.

BTI’s data indicates that the “cleanest” platforms continue to be Kraken, Poloniex, Coinbase and Upbit.

At the other extreme, OKEx and Bibox appear to have the highest percentage of wash trading among the top 40.

While the wash traded volumes on these platforms exceed 75%, according to BTI, their real volumes (calculated without wash trades) still consistently place them among the top 20 exchanges globally.

Bitcoin’s wash trading level is roughly 50%

Among other cryptocurrencies, Bitcoin (BTC) is being wash traded just under 50%, according to live tracking data from BTI. Ethereum levels are at about 75%, XRP at 55%, and Litecoin at 74%. BTI claims that most of this inflated volume is attributable to activity on OKEx, Bibox and Huobi.

The most heavily wash traded tokens among the top 25 cryptocurrencies are Ethereum Classic, Monero and Dash at over 80% fake volume, which BTI attributes largely to OKEx, Bibox and Bithumb.

Maker Dao, Binance Coin and LEO as the least wash traded tokens in the top 25 coins — all with fake volume rates of under 25%.

OKex challenges BTI’s allegations

As Cointelegraph reported, OKEx has recently hit back at BTI, claiming that the Institute’s “research methodology is not transparent and they do not provide data to back up their claims.”

OKEx contends that, given its nature as a crypto derivatives platform, its characteristic patterns of trades — from “hedge funds, proprietary traders and high-frequency trading firms” — follow a different pattern to spot-only venues.

It has therefore argued that BTI’s use of “retail-oriented parameters such as website/mobile traffic” in its research is “an apple-to-orange comparison.”

In March, the topic of was trading has already become a hotly contested issue following a series of bombshell reports that revealed the apparent prevalence of manipulative trading practices in the industry.