New Delhi, Nov. 19 -- Even as online platforms make corporate bonds more accessible to retail investors, the market regulator has stepped in to warn that not all players are playing by the rules.

The Securities and Exchange Board of India (Sebi) cautioned investors against using unregistered online bond platform providers (OBPP), bringing into focus fintech companies and stockbrokers that are providing bond-dealing services without the regulator's approval."It has been observed that certain entities, including fintech companies and stock brokers, are offering services in the nature of OBPPs without obtaining due registration from the Stock Exchanges," Sebi said in a notice on Wednesday.

Such entities, the market regulator said, are oper...