It is understood the FCA considers this to also cover platforms involved in selling investment products and providing a service, meaning they will be the recipients of information on target market from product manufacturers and will need to provide information on sales.
Simon Farrant, head of proposition at FundsNetwork, said his platform provides the information necessary to fund management companies and had been doing so for "many years" before Mifid II came into effect.
He said: "This might be where you find the distinction lies. If you have been around as a platform for a long time then fund managers will have been banging on your door many years before Mifid II was through about, asking for more information.
"What it may do at the margins is it may cause some fund managers to say 'we don't want to be listed by this platform because they will leave us in a weakened position to comply with our Mifid II objectives'. But I have not heard about that happening yet and the fund managers will be very reluctant to take that decision."
Mr Farrant said fund managers might be more likely to make this decision if a larger proportion of their sales came through platforms which did not provide data back and forth.
A spokesman for Standard Life, which owns its Wrap platform as well as Elevate, said: "The Mifid regulations dictate that it’s the responsibility of advisers as distributors of Mifid instruments to ensure that any investment choices they make are aligned to the needs of their clients. Advisers therefore need to be in control of their investment choices - platforms are unable to take on this obligation.
"To help support advisers in meeting this obligation, we make the necessary target market and cost information available on an instrument by instrument basis via our websites."
Ascentric, Novia and AJ Bell all said they would be helping to provide data back and forth.
A spokesman for AJ Bell said there were "certainly inconsistencies" in the way platforms were addressing this issue while Ascentric, which also acknowledged there were problems in this area, suggested advisers could use a data aggregator to address this.
Ian Cornwall, director of regulation at the Personal Investment Management and Financial Advice Association, said he would be attending a meeting in Paris in the next few weeks to attempt to clarify how these requirements could be met in a consistent manner across the EU.
He said: "What we are seeing is some platforms will not provide information back to the manufacturer and some might be more willing to report information. Different platforms are taking different views on that.