Fund managers that pass the cost of research on to clients rather than absorbing it are charging up to 7.5 times more, according to fresh data.
The Financial Times reports data from Frost Consulting, which show the impact of Mifid II rules that were introduced in January.
The consulting firm analysed 3,000 funds and 350 asset managers and finds equity funds investing in emerging markets that use client money to pay for research are spending 7.5 times more on average than firms that absorb the cost.
The FT reports that for equity funds investing in Europe and North America the result was 3.8 times and 2.7 times, respectively.
Under Mifid II legislation asset managers need to disclose how much they pay brokers for investment research separately from trading costs. Firms have to declare whether they pass these costs to their clients or pay for it out of their own pocket.
Paris-based asset manager Carmignac is one firm that is passing research costs on to its clients.
In the UK Woodford Investment Management, Jupiter, Vanguard, Columbia Threadneedle and M&G are among the asset managers that have said they will absorb costs.