Britain’s banks and insurers must take the lead in spelling out how they will use data collected from customers or they could face new rules, Financial Conduct Authority Chair Charles Randell said on Wednesday.

Financial firms have been using Big Data on customers, which can include social media use, for example to price motor or health insurance more accurately. But the trend has worried regulators and consumer groups.

The use of Big Data requires good communication so that consumers understand and accept a firm’s approach to using their data and don’t end up being “disenfranchised,” Randell said.

“By good communication, I don’t mean pages and pages of obscure disclosures, disclaimers and consents. I mean short and readable statements which make it clear what firms will and won’t do with their customers’ data,” Randell told a Reuters Newsmaker event.

“These need to be developed with consumers, not imposed on them,” Randell said in his first major speech since becoming chair of the FCA in April.

“A number of firms do this already but many do not. Should all businesses have a data charter? Should these be developed through voluntary codes of practice? Will the industry take the lead or should they be a regulatory requirement?”

Any regulation would aim not to be too prescriptive given the pace of technological change, Randell said in answer to a question. “I don’t see this as an area where a 13-foot-high rule book would be your best approach.”

‘Robust Procedures’

Matt Cullen, head of strategy, data and analytics at the Association of British Insurers, said that while Big Data could bring benefits for customers, “we’re also aware that the issues it raises need to be carefully considered.” He added that insurers would “always have robust procedures in place.”

In September 2016, the FCA dropped plans for a formal review of whether Big Data might make it harder or more expensive for some customers to buy a car or home insurance, but said it would look at the risk of some customers being excluded.

Randell said the power of Big Data corporations and their central place in providing services that are now essential in everyday lives raise significant questions about the adequacy of global frameworks for competition and regulation.

Britain’s information regulator said on Wednesday it intends to fine Facebook500,000 pounds ($663,550), the maximum possible, for breaches of data protection law as the watchdog investigates how millions of users’ data was improperly accessed by consultancy Cambridge Analytica.

“The ordinary consumer may in practice have no choice in whether to deal with these corporations on terms which are non-negotiable and are often too general to be well understood. And without access to the data which consumers have signed – or clicked – away, new businesses may find it very difficult to compete,” Randell said.

“If you add all these factors together, they call into question the adequacy of the traditional liberal approach to the relationship between financial services firms and their customers. And regulation is central because it will help define whether AI and Big Data liberate customers, or disenfranchise them.”