Net outflows from cryptocurrency funds totaled $44 million for the week ending June 25, marking the fourth consecutive week of redemptions.
The amount of money leaving was significantly less than the previous, record week of $141 million.
"This traditionally bullish signal should be interpreted with caution and in the context of other indicators," one analyst said.
The fewer coins available for sale on exchanges, the better the chance of markets rising.
Investors have been diversifying out of bitcoin and into altcoin investment products, according to CoinShares.